A project manager first creates an assumption log during the Develop Project Charter process and records all project assumptions and constraints.
During which of the following processes is the assumptions log updated and/or new assumptions and constraints added during the project execution?
A. Monitor and Control Project Work
B. Close Project or Phase
C. Direct and Manage Project Work
D. Collect Requirements

Correct answer is C.
During the Direct and Manage Project Work process, new assumptions and constraints are added to the assumption log.
And the status of existing assumptions and constraints may be updated and closed out.
The other process do not directly update the assumptions log as an output of the process.
PMBOK Pages 81 and 97.
Hey there. I found your web site by the use of Google whilst searching for a related subject, your site came up. It appears to be good. I’ve bookmarked it in my google bookmarks to visit then.