You company has a Microsoft 365 subscription that contains the teams shown in the following exhibit.
Guest users report that they cannot create posts in Monthly Reports.
You need to ensure that the guest users can post to Monthly Reports.
What should you do?
A. From the Microsoft Teams client, modify the privacy setting.
B. From the Microsoft Teams admin center, modify the Guest access settings.
C. From the Microsoft Teams client, modify the channel moderation preferences.
D. From the Microsoft Teams admin center, modify the messaging policy.
I didn’t find anything limiting GUEST from posting under Messaging policies. So I would agree with B.
Answer B is correct!
Messaging
Turn on or turn off settings for guests in chats or channel conversations.
Answer C
In Microsoft Teams, team owners can turn on moderation for a standard channel to control who can start new posts and reply to posts in that channel.
https://docs.microsoft.com/en-us/microsoftteams/manage-channel-moderation-in-teams
I think C is correct answer. Sounds like user is able to access that team and channel but he is not able to post. This is Channel moderation preference that can be switched from “Everyone except guests can start a new post” to “Everyone can start a new post”.