Exam Certified Platform App Builder topic 1 question 499 discussion

package installation failed in production after successfully installing it in a full copy sandbox, which is an exact match for production. In such cases, the most common reason for the installation failure in production is Apex unit test failures. Salesforce requires that all Apex tests pass successfully before allowing the installation of a package into a production environment. D is the Answer

Because they explicitly say "exact match for production" I feel D is the best answer.

question says "full copy sandbox that is an exact match for production" so it means all features and license is the same with prod. The only issue might be unit tests D

A your sandbox may have been updated to a new release before that same update hits production. So the orgs are incompatible even though its a full copy https://developer.salesforce.com/forums/?id=9060G0000005o3BQAQ#:~:text=This%20occurs%20when%20you%20try,upgraded%20to%20the%20current%20release.

A or D?