Hi, I would like to have your comment on this question please

Your Customer calls you on the phone and informs you of a minor change to a requirement on the project. What is the first thing that should be done  ?

A. Analyze the request and it's consequences to the project

B. Instruct your enginieer to implement this minor Change

C. Ask the customer to provide a formal change request

D. Note it in the weekly status Report.