If you have a security recommendation that is not applicable for your environment, and you don’t want to negatively affect your secure score, which option is the most appropriated to use?

Answer options:

A.Create an exemption for the recommendation
B.Disable the recommendation
C.Create a new resource group and exempt the recommendation from the resource group
D.Create a custom recommendation

Correct Answer: B Option B is correct. It is recommended for disabling recommendations when they`re inapplicable in your environment.
Option A, C & D are incorrect. It is not possible and appropriate to do them.
Reference: 

https://docs.microsoft.com/en-us/azure/security-center/security-center-recommendations