USMLE - Question 2 (with answer and explanation)

The United States Medical Licensing Examination® (USMLE®) is a three-step examination for medical licensure in the United States and is sponsored by the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners® (NBME®). Physicians with an M.D. degree are required to pass this examination before being permitted to practice medicine in the United States; see below for requirements of physicians with a D.O. degree.