Answer:
Option-A
Explanation:
In the given question, since the examiner has mentioned the time that the factor the researcher should include during the development of a new drug is "the placebo". A placebo is used during the experiment as control by and its effect depend on the expectations of the patient since the placebo does not contain the active drugs.
The FDA approval, informed consent and the information are not used until the study is going on.
Thus, Option-A is the correct answer.