In order to obtain and comply with certifications, independent external audits must be performed and satisfied.
Although some testing of certification controls can be part of an internal audit, they will not satisfy requirements.

The gap analysis determines if there are any differences between the actual configurations in use on systems and the policies that govern what the configurations are expected or mandated to be. The other terms provided are all similar to the correct answer ("findings" in particular is often used to articulate deviations in configurations), but gap analysis is the official term used.