Final answer:
The protocol most likely to require IRB review is D) Drug trial, as it involves a controlled experiment and human participants with potential risks and thus necessitates ethical oversight and approval from an Institutional Review Board.
Step-by-step explanation:
Among the options provided, D) Drug trial is the protocol that is most likely to require Institutional Review Board (IRB) review. The IRB is a committee of administrators, scientists, and community members that reviews proposals for research involving human participants to ensure ethical standards and participant safety. Drug trials involve conducting a controlled experiment to determine whether a drug is deemed to be suitable for administration to humans based on an acceptable risk assessment, and therefore, they require close scrutiny and approval by an IRB. Other options such as A) Administrative study, B) Quality improvement project, and C) Case report may not necessarily require IRB review, as they typically do not involve the same level of risk to human subjects as clinical research like drug trials do.