You have a Microsoft 365 E5 subscription that uses Teams. You have a team named Team1 that contains guest users. You need to ensure that the members of Team1 are prevented from sharing sensitive…

A data loss prevention (DLP) policy can be configured in Microsoft 365 to detect and prevent the sharing of sensitive information types, such as financial data or personal identifiable information, within Teams private chats and channels. By setting a DLP policy, you can specifically restrict content from being shared with guest users, ensuring sensitive data does not leave the organization's control.

A messaging policy controls the features available within Teams chats and channels, like read receipts or message editing, but does not prevent the sharing of specific sensitive content.

An information barrier policy restricts communication and collaboration between specific groups of users for compliance reasons, but it is not primarily designed to prevent sensitive information from being shared based on its content with guest users.

A sensitivity label policy classifies and protects documents and emails by applying encryption or access restrictions, but it does not actively monitor and block sensitive content sharing in real-time within Teams chats or channels.