Final answer:
Cholesterol is used to synthesize bile acids, and it is essential for proper bodily functions, including the production of Vitamin D and as a component of cell membranes.
Step-by-step explanation:
The correct answer to the student's question is: c. It is used to synthesize bile acids. Cholesterol is an essential component in the body that plays multiple roles. It is synthesized mainly in the liver and is crucial for the production of steroid hormones like testosterone and estradiol. Cholesterol is necessary for the body's proper functioning and is a key component of animal cell plasma membranes, making up part of the phospholipid bilayer. Additionally, cholesterol is a precursor to Vitamin D and is involved in synthesizing bile salts, which are vital in the emulsification and absorption of fats by cells.