Which position involves lying on the left side with the right knee drawn up?

The position described as lying on the left side with the right knee drawn up is known as Sim's position. This position is commonly used in medical settings for various procedures, including administering enemas, conducting rectal examinations, and providing comfort to patients who may need assistance in assuming a position that reduces pressure on certain areas of the body.

In Sim's position, the left side of the body is down while the right leg is often flexed and drawn up at the knee, which helps to open the rectal area for better access. This specific alignment also aids in comfort and support.

In contrast, the supine position refers to lying flat on the back; Fowler's position involves sitting up at various angles with the back supported; and the prone position requires lying face down. Each of these positions serves different purposes in patient care and comfort, but for the description given, Sim's position is the correct choice.