Final answer:
The temporalis muscle is responsible for retracting and closing the jaw in the human body, working alongside the masseter muscle which is the primary muscle involved in chewing. The correct answer is option C .
Step-by-step explanation:
In the human body, the muscle responsible for closing and retracting the mandible, or jaw, is the temporalis muscle. The question asks to identify the muscle from a list, and Option C) Temporalis is the correct answer. The masseter muscle is the main muscle for chewing and works to elevate the mandible to close the mouth. The masseter and temporalis muscles work in tandem to perform the actions needed for mastication.
When we chew, muscles are involved in a complex series of actions that allow us to bite, grind, and swallow food. The masseter muscle is the most visible one when we clench our teeth; it is located at the angle of the jaw and is commonly known for its power in elevating the mandible. The temporalis muscle complements the masseter by retracting the jaw, which you can feel by touching your temple area as you chew.
Additional muscles, such as the medial pterygoid and lateral pterygoid, also assist in moving the mandible during the chewing process, providing the ability to move the jaw from side to side and even forwards, further aiding mastication. While not directly involved in the question, understanding these muscles provides a more complete picture of the intricate system that controls jaw movement. For example, the medial pterygoid helps primarily in the side-to-side motion, which is also crucial for effective grinding of food.