Question

why do we not know for sure how many muscles there are in the human body? the body continuously breaks down muscles to repair. the body continuously builds new muscles. there are different types of muscles, its difficult to narrow them down.

Explanation:

To determine why we don't know the exact number of human body muscles, we analyze each option:

• The first option (muscle breakdown for repair) relates to muscle maintenance, not counting difficulty.
• The second option (building new muscles) is about muscle growth, not counting.
• The third option notes different muscle types (e.g., skeletal, smooth, cardiac, and variations within) make classification and counting challenging, as defining what constitutes a distinct muscle can be ambiguous.

Answer:

C. There are different types of muscles, it's difficult to narrow them down. (Note: Assuming the third option is labeled C; adjust the identifier if the original options have different labels, but the text of the correct option is "There are different types of muscles, it's difficult to narrow them down.")