How does the prefix "ab-" modify a term in medical terminology?

The prefix "ab-" is derived from Latin and specifically means "away from." In medical terminology, this prefix is commonly used to describe processes or conditions that involve moving away from a particular structure or reference point in the body. For example, in the term "abduction," which refers to the movement of a limb away from the midline of the body, the prefix "ab-" clearly indicates the direction of movement.

Understanding how "ab-" modifies a term helps clarify the nature of medical conditions, procedures, or anatomical references, as it sets a foundation for interpreting various medical terms accurately. The other choices represent different directions or concepts, but they do not align with the true meaning of the prefix "ab-."