You are the IT administrator of an organization with a Microsoft 365 subscription and Microsoft 365 E5 licenses assigned to your users. Your computers run Windows 7 SP1 Enterprise. You want to onboard your devices to Microsoft Defender for Endpoint. What onboarding method should you choose? 

Answer options:

A.Through a third-party solution
B.Through Mobile Device Management (including Microsoft Intune)
C.By creating a Group Policy
D.By installing and configuring Microsoft Monitoring Agent on the devices.

Correct Answer: D 
To onboard devices on down-level operating systems, you must first Configure and update System Center Endpoint Protection clients, and then Install and configure Microsoft Monitoring Agent (MMA) to report sensor data to Defender for Endpoint.
Option A is incorrect. This is not possible for Windows 7 devices, but you can use a third party solution to onboard your non-windows devices.
Option B is incorrect. This is a valid onboarding method, but only applicable to Windows 10 devices.
Option C is incorrect. This is a valid onboarding method, but only applicable to Windows 10 devices.
Reference:
To know more about onboarding devices to defender for endpoint, please refer to the link below: 

https://docs.microsoft.com/en-us/microsoft-365/security/defender-endpoint/onboard-downlevel?view=o365-worldwide