Which prefix means "before, in front of"?

The prefix "ante-" is derived from Latin, meaning "before" or "in front of." In medical terminology, this prefix is commonly used to describe conditions or positions that occur prior to or in advance of something else. For instance, in terms like "antenatal," it refers to the period before birth, highlighting how the prefix indicates the temporal aspect of being prior to an event.

The other prefixes have distinct meanings that do not align with the concept of "before." "Anti-" typically denotes opposition or counteraction, "brady-" refers to slowness, and "auto-" signifies self or automatic processes. Therefore, "ante-" is the correct choice as it explicitly conveys the idea of being in front of or prior to something else.