Answer is C. Since when you are auditing you are checking for whether the quality process are being followed, You are not checking the work results or work products.

Hi Moranz,

I would like to add few comments on these one are that:

Quality Audits are tool of perform Quality Assurance that checks to see if the process is being followed.

choice:b - is referring to inspection of work results, which is a tool of Perform Quality Control.

Hope this will clarify enough.

thx. good louck for ur exam.

The words structured review is the big hint in C. All audits are structured reviews of some nature.

Moranz,
It's good to break down each answer.

a - An audit is a tool, not a group of people. People can USE the tool, but they are not the tool itself.
b - Inspecting the work results (or work product) is done after the results/product are complete. According to PMI, Quality Assurance is done while creating the product, not after. That is Quality Control. A way to help remember these is that QA (Quality Audit) is done in QA (Quality Assurance). Also, QA comes before QC.
c - correctly identified by others.
d - Identifying quality requirements would occur in Plan Quality, before we create deliverables or perform any kind of review.