Question

a reflex is: an inherited skill. an innate preference. a genetic motor tendency. an involuntary response to a particular stimulus.

Explanation:

A reflex is an automatic, involuntary reaction to a specific stimulus. It doesn't require conscious thought and is a basic physiological response. It's not an inherited skill (which implies more complex learned - like behavior), not an innate preference (which is about likes/dislikes), and not just a genetic motor tendency (it's more immediate and stimulus - response based).

Answer:

an involuntary response to a particular stimulus.