After Achieving Necessary Clearances and Approval, a Researcher Investigating Perceptions

After achieving necessary clearances and approval, a researcher investigating perceptions of adults with diminished mental capacity should do which of the following:

A) Present subjects with the IRB paperwork to help them understand the full extent of the research.
B) Begin testing research subjects immediately.
C) Rewrite and discuss a consent form in a level of language that the research subject can be expected to understand.
D) Explain the research goals solely to the guardian or parent, ignoring the research subject.