I guess just pick your answer and hope for the best? What a terribly written question. My guess is A because it doesn't answer the question of HOW to exclude. Just adding a P2 license doesn't exclude and it doesn't ask, "what do you do first". Still, is there some way of doing this without P2?
For either the Defender Cloud Security Posture Management (CSPM) or Defender for Servers P2 plan, select Settings.
For either the Defender Cloud Security Posture Management (CSPM) or Defender for Servers P2 plan, select Settings.
From MS:
For either the Defender Cloud Security Posture Management (CSPM) or Defender for Servers P2 plan, select Settings.
Enter the tag name and value that applies to the machines that you want to exempt. You can enter multiple tag:value pairs.
https://learn.microsoft.com/en-us/azure/defender-for-cloud/enable-agentless-scanning-vms#exclude-machines-from-scanning