Final answer:
The prone position refers to lying on the stomach with the face down, contrasting with the supine position where the body lies on the back with the face up.
Step-by-step explanation:
In a medical examination, the prone position is defined as the body being oriented with the face and torso down. Therefore, the correct option for the student's question is B) Lying on the stomach with face down. This position contrasts with the supine position, which refers to lying on the back with the face upward. When a body is in the anatomical position, it is standing upright, with feet at shoulder width and parallel, toes forward, upper limbs are held out to the side, and palms facing forward. Knowing these positions is crucial for proper description and understanding of body orientation in medical settings.