Here is a weird question i found online - 

Where can you find Stakeholders Communication Requirements - 

1) Stakeholder Register

2) Stakeholder Manaagement Plan

3) Communication Management Plan

4) Project Management Plan

How to answer it ?

The register talks about stakeholders requirements and some of those requirements may be communication related.

The Stakeholder Mgmt Plan talks about the communication requirements.

The Communication Management Plan talks about the communication requirements.