Org must block legacy authentication protocols for Microsoft 365. Best control?
Select an answer to reveal the explanation.
Short Explanation and Infographic
Legacy auth is the side door that skips modern MFA. CA block on legacy clients slams it shut.
Full explanation below image
Full Explanation
Correct Answer — A
Conditional Access can target legacy authentication clients and block them, forcing modern auth paths compatible with MFA.
Why B is wrong: Non-enforcing.
Why C is wrong: Storage not auth.
Why D is wrong: POP expands legacy surface.
Exam tip: Kill legacy auth → CA block legacy clients.