A:Answer Yes, it does have a built in microphone.
However, the microphone is disabled by default and must be turned on within the Microsoft Accessory Center app that Windows 10 installs when you plug the webcam into your computer. When you toggle it on, it also displays a prompt to warn you that the microphone isn't Microsoft Teams certified and to confirm that you want to enable it.
This is very strange given that this is the MICROSOFT Modern Webcam with MICROSOFT Teams logos on the front and back of the box.