Azure Activity Logs (now also called Azure Monitor activity log) record subscription-level events, but user sign-in details are specifically in Azure AD Sign-in logs, which are part of Azure Active Directory reporting. However, the question asks about Azure logs; the most appropriate is Azure AD Sign-in logs, but since that's not an option, the closest is Azure Activity Logs which can capture management events, but not sign-ins. Actually, Azure AD Sign-in logs are the correct source.
But given options, if only Azure Activity Logs is present, it's partially correct. The typical answer is Azure AD Sign-in logs. Since the question says "Azure log", the best choice is Azure Activity Logs as it's within Azure Monitor, but it's not precise.
Let's adjust options accordingly. I'll assume Azure AD Sign-in logs is not listed; I'll create a plausible distractor. Actually, in real exam, they expect Azure AD Sign-in logs.
I'll make sure one option says "Azure AD Sign-in logs". But the stem says "Azure log", so I'll include it. Let me redo: The correct answer should be Azure AD Sign-in logs.
I'll set that as option A.