Final answer:
The FDA requires investigators to inform the subject's primary physician about their participation in a clinical trial if the subject has a PCP and if the subject agrees to the primary physician being informed.
Step-by-step explanation:
The correct answer to the question is True. The FDA (Food and Drug Administration) requires investigators to inform the subject's primary physician about their participation in a clinical trial if the subject has a PCP (primary care physician) and if the subject agrees to the primary physician being informed. This requirement ensures that the subject's primary physician is aware of their participation in the trial and can provide appropriate care and oversight. It is an important step in maintaining the subject's safety and well-being during the trial.