diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java b/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java
index fe9bbba..56202fd 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsFeatureFlags.java
@@ -118,6 +118,14 @@
     }
 
     /**
+     * Indicates whether {@link #NSD_KNOWN_ANSWER_SUPPRESSION} is enabled, including for testing.
+     */
+    public boolean isKnownAnswerSuppressionEnabled() {
+        return mIsKnownAnswerSuppressionEnabled
+                || isForceEnabledForTest(NSD_KNOWN_ANSWER_SUPPRESSION);
+    }
+
+    /**
      * The constructor for {@link MdnsFeatureFlags}.
      */
     public MdnsFeatureFlags(boolean isOffloadFeatureEnabled,
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java b/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java
index 96a59e2..ed0bde2 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsRecordRepository.java
@@ -538,7 +538,7 @@
     }
 
     private boolean isTruncatedKnownAnswerPacket(MdnsPacket packet) {
-        if (!mMdnsFeatureFlags.mIsKnownAnswerSuppressionEnabled
+        if (!mMdnsFeatureFlags.isKnownAnswerSuppressionEnabled()
                 // Should ignore the response packet.
                 || (packet.flags & MdnsConstants.FLAGS_RESPONSE) != 0) {
             return false;
@@ -745,7 +745,7 @@
             // RR TTL as known by the Multicast DNS responder, the responder MUST
             // send an answer so as to update the querier's cache before the record
             // becomes in danger of expiration.
-            if (mMdnsFeatureFlags.mIsKnownAnswerSuppressionEnabled
+            if (mMdnsFeatureFlags.isKnownAnswerSuppressionEnabled()
                     && isKnownAnswer(info.record, knownAnswerRecords)) {
                 continue;
             }
diff --git a/service-t/src/com/android/server/connectivity/mdns/MdnsReplySender.java b/service-t/src/com/android/server/connectivity/mdns/MdnsReplySender.java
index a46be3b..db3845a 100644
--- a/service-t/src/com/android/server/connectivity/mdns/MdnsReplySender.java
+++ b/service-t/src/com/android/server/connectivity/mdns/MdnsReplySender.java
@@ -145,7 +145,7 @@
     public void queueReply(@NonNull MdnsReplyInfo reply) {
         ensureRunningOnHandlerThread(mHandler);
 
-        if (mMdnsFeatureFlags.mIsKnownAnswerSuppressionEnabled) {
+        if (mMdnsFeatureFlags.isKnownAnswerSuppressionEnabled()) {
             mDependencies.removeMessages(mHandler, MSG_SEND, reply.source);
 
             final MdnsReplyInfo queuingReply = mSrcReplies.remove(reply.source);
@@ -231,7 +231,7 @@
         @Override
         public void handleMessage(@NonNull Message msg) {
             final MdnsReplyInfo replyInfo;
-            if (mMdnsFeatureFlags.mIsKnownAnswerSuppressionEnabled) {
+            if (mMdnsFeatureFlags.isKnownAnswerSuppressionEnabled()) {
                 // Retrieve the MdnsReplyInfo from the map via a source address, as the reply info
                 // will be combined or updated.
                 final InetSocketAddress source = (InetSocketAddress) msg.obj;
diff --git a/tests/cts/net/src/android/net/cts/NsdManagerTest.kt b/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
index 6db372f..ce2c2c1 100644
--- a/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
+++ b/tests/cts/net/src/android/net/cts/NsdManagerTest.kt
@@ -1716,6 +1716,177 @@
         }
     }
 
+    @Test
+    fun testReplyWhenKnownAnswerSuppressionFlagSet() {
+        // The flag may be removed in the future but known-answer suppression should be enabled by
+        // default in that case. The rule will reset flags automatically on teardown.
+        deviceConfigRule.setConfig(NAMESPACE_TETHERING, "test_nsd_known_answer_suppression", "1")
+        deviceConfigRule.setConfig(NAMESPACE_TETHERING, "test_nsd_unicast_reply_enabled", "1")
+
+        val si = makeTestServiceInfo(testNetwork1.network)
+
+        // Register service on testNetwork1
+        val registrationRecord = NsdRegistrationRecord()
+        var nsResponder: NSResponder? = null
+        tryTest {
+            registerService(registrationRecord, si)
+            val packetReader = TapPacketReader(Handler(handlerThread.looper),
+                    testNetwork1.iface.fileDescriptor.fileDescriptor, 1500 /* maxPacketSize */)
+            packetReader.startAsyncForTest()
+
+            handlerThread.waitForIdle(TIMEOUT_MS)
+            /*
+            Send a query with a known answer. Expect to receive a response containing TXT record
+            only.
+            Generated with:
+            scapy.raw(scapy.DNS(rd=0, qr=0, aa=0, qd =
+                    scapy.DNSQR(qname='_nmt123456789._tcp.local', qtype='PTR',
+                            qclass=0x8001) /
+                    scapy.DNSQR(qname='NsdTest123456789._nmt123456789._tcp.local', qtype='TXT',
+                            qclass=0x8001),
+                    an = scapy.DNSRR(rrname='_nmt123456789._tcp.local', type='PTR', ttl=4500,
+                            rdata='NsdTest123456789._nmt123456789._tcp.local')
+            )).hex()
+            */
+            val query = HexDump.hexStringToByteArray("0000000000020001000000000d5f6e6d74313233343" +
+                    "536373839045f746370056c6f63616c00000c8001104e7364546573743132333435363738390" +
+                    "d5f6e6d74313233343536373839045f746370056c6f63616c00001080010d5f6e6d743132333" +
+                    "43536373839045f746370056c6f63616c00000c000100001194002b104e73645465737431323" +
+                    "33435363738390d5f6e6d74313233343536373839045f746370056c6f63616c00")
+            replaceServiceNameAndTypeWithTestSuffix(query)
+
+            val testSrcAddr = makeLinkLocalAddressOfOtherDeviceOnPrefix(testNetwork1.network)
+            nsResponder = NSResponder(packetReader, mapOf(
+                    testSrcAddr to MacAddress.fromString("01:02:03:04:05:06")
+            )).apply { start() }
+
+            packetReader.sendResponse(buildMdnsPacket(query, testSrcAddr))
+            // The reply is sent unicast to the source address. There may be announcements sent
+            // multicast around this time, so filter by destination address.
+            val reply = packetReader.pollForMdnsPacket { pkt ->
+                pkt.isReplyFor("$serviceName.$serviceType.local", DnsResolver.TYPE_TXT) &&
+                        !pkt.isReplyFor("$serviceType.local", DnsResolver.TYPE_PTR) &&
+                        pkt.dstAddr == testSrcAddr
+            }
+            assertNotNull(reply)
+
+            /*
+            Send a query with a known answer (TTL is less than half). Expect to receive a response
+            containing both PTR and TXT records.
+            Generated with:
+            scapy.raw(scapy.DNS(rd=0, qr=0, aa=0, qd =
+                    scapy.DNSQR(qname='_nmt123456789._tcp.local', qtype='PTR',
+                            qclass=0x8001) /
+                    scapy.DNSQR(qname='NsdTest123456789._nmt123456789._tcp.local', qtype='TXT',
+                            qclass=0x8001),
+                    an = scapy.DNSRR(rrname='_nmt123456789._tcp.local', type='PTR', ttl=2150,
+                            rdata='NsdTest123456789._nmt123456789._tcp.local')
+            )).hex()
+            */
+            val query2 = HexDump.hexStringToByteArray("0000000000020001000000000d5f6e6d7431323334" +
+                    "3536373839045f746370056c6f63616c00000c8001104e736454657374313233343536373839" +
+                    "0d5f6e6d74313233343536373839045f746370056c6f63616c00001080010d5f6e6d74313233" +
+                    "343536373839045f746370056c6f63616c00000c000100000866002b104e7364546573743132" +
+                    "333435363738390d5f6e6d74313233343536373839045f746370056c6f63616c00")
+            replaceServiceNameAndTypeWithTestSuffix(query2)
+
+            packetReader.sendResponse(buildMdnsPacket(query2, testSrcAddr))
+            // The reply is sent unicast to the source address. There may be announcements sent
+            // multicast around this time, so filter by destination address.
+            val reply2 = packetReader.pollForMdnsPacket { pkt ->
+                pkt.isReplyFor("$serviceName.$serviceType.local", DnsResolver.TYPE_TXT) &&
+                        pkt.isReplyFor("$serviceType.local", DnsResolver.TYPE_PTR) &&
+                        pkt.dstAddr == testSrcAddr
+            }
+            assertNotNull(reply2)
+        } cleanup {
+            nsResponder?.stop()
+            nsdManager.unregisterService(registrationRecord)
+            registrationRecord.expectCallback<ServiceUnregistered>()
+        }
+    }
+
+    @Test
+    fun testReplyWithMultipacketWhenKnownAnswerSuppressionFlagSet() {
+        // The flag may be removed in the future but known-answer suppression should be enabled by
+        // default in that case. The rule will reset flags automatically on teardown.
+        deviceConfigRule.setConfig(NAMESPACE_TETHERING, "test_nsd_known_answer_suppression", "1")
+        deviceConfigRule.setConfig(NAMESPACE_TETHERING, "test_nsd_unicast_reply_enabled", "1")
+
+        val si = makeTestServiceInfo(testNetwork1.network)
+
+        // Register service on testNetwork1
+        val registrationRecord = NsdRegistrationRecord()
+        var nsResponder: NSResponder? = null
+        tryTest {
+            registerService(registrationRecord, si)
+            val packetReader = TapPacketReader(Handler(handlerThread.looper),
+                    testNetwork1.iface.fileDescriptor.fileDescriptor, 1500 /* maxPacketSize */)
+            packetReader.startAsyncForTest()
+
+            handlerThread.waitForIdle(TIMEOUT_MS)
+            /*
+            Send a query with truncated bit set.
+            Generated with:
+            scapy.raw(scapy.DNS(rd=0, qr=0, aa=0, tc=1, qd=
+                    scapy.DNSQR(qname='_nmt123456789._tcp.local', qtype='PTR',
+                            qclass=0x8001) /
+                    scapy.DNSQR(qname='NsdTest123456789._nmt123456789._tcp.local', qtype='TXT',
+                            qclass=0x8001)
+            )).hex()
+            */
+            val query = HexDump.hexStringToByteArray("0000020000020000000000000d5f6e6d74313233343" +
+                    "536373839045f746370056c6f63616c00000c8001104e7364546573743132333435363738390" +
+                    "d5f6e6d74313233343536373839045f746370056c6f63616c0000108001")
+            replaceServiceNameAndTypeWithTestSuffix(query)
+            /*
+            Send a known answer packet (other service) with truncated bit set.
+            Generated with:
+            scapy.raw(scapy.DNS(rd=0, qr=0, aa=0, tc=1, qd=None,
+                    an = scapy.DNSRR(rrname='_test._tcp.local', type='PTR', ttl=4500,
+                            rdata='NsdTest._test._tcp.local')
+            )).hex()
+            */
+            val knownAnswer1 = HexDump.hexStringToByteArray("000002000000000100000000055f74657374" +
+                    "045f746370056c6f63616c00000c000100001194001a074e736454657374055f74657374045f" +
+                    "746370056c6f63616c00")
+            replaceServiceNameAndTypeWithTestSuffix(knownAnswer1)
+            /*
+            Send a known answer packet.
+            Generated with:
+            scapy.raw(scapy.DNS(rd=0, qr=0, aa=0, qd=None,
+                    an = scapy.DNSRR(rrname='_nmt123456789._tcp.local', type='PTR', ttl=4500,
+                            rdata='NsdTest123456789._nmt123456789._tcp.local')
+            )).hex()
+            */
+            val knownAnswer2 = HexDump.hexStringToByteArray("0000000000000001000000000d5f6e6d7431" +
+                    "3233343536373839045f746370056c6f63616c00000c000100001194002b104e736454657374" +
+                    "3132333435363738390d5f6e6d74313233343536373839045f746370056c6f63616c00")
+            replaceServiceNameAndTypeWithTestSuffix(knownAnswer2)
+
+            val testSrcAddr = makeLinkLocalAddressOfOtherDeviceOnPrefix(testNetwork1.network)
+            nsResponder = NSResponder(packetReader, mapOf(
+                    testSrcAddr to MacAddress.fromString("01:02:03:04:05:06")
+            )).apply { start() }
+
+            packetReader.sendResponse(buildMdnsPacket(query, testSrcAddr))
+            packetReader.sendResponse(buildMdnsPacket(knownAnswer1, testSrcAddr))
+            packetReader.sendResponse(buildMdnsPacket(knownAnswer2, testSrcAddr))
+            // The reply is sent unicast to the source address. There may be announcements sent
+            // multicast around this time, so filter by destination address.
+            val reply = packetReader.pollForMdnsPacket { pkt ->
+                pkt.isReplyFor("$serviceName.$serviceType.local", DnsResolver.TYPE_TXT) &&
+                        !pkt.isReplyFor("$serviceType.local", DnsResolver.TYPE_PTR) &&
+                        pkt.dstAddr == testSrcAddr
+            }
+            assertNotNull(reply)
+        } cleanup {
+            nsResponder?.stop()
+            nsdManager.unregisterService(registrationRecord)
+            registrationRecord.expectCallback<ServiceUnregistered>()
+        }
+    }
+
     private fun makeLinkLocalAddressOfOtherDeviceOnPrefix(network: Network): Inet6Address {
         val lp = cm.getLinkProperties(network) ?: fail("No LinkProperties for net $network")
         // Expect to have a /64 link-local address