B. a Log Analytics workspace
C. Azure Information Protection
Explanation:
To on-board Azure Sentinel, you first need to connect to your security sources. Azure Sentinel comes with a number of connectors for Microsoft solutions, including Microsoft 365 Defender solutions, and Microsoft 365 sources, including Office 365, Azure AD, Microsoft Defender for Identity, and Microsoft Cloud App Security, etc.
Reference: https://docs.microsoft.com/en-us/azure/sentinel/overview