Question

which action is a response to external stimuli?
eating when hungry
wearing sunglasses to protect eyes from uv rays
drinking when thirsty
breathing hard when exercising because of a drop in oxygen levels

Explanation:

External stimuli are factors originating outside the body. The other options respond to internal bodily needs (hunger, thirst, internal oxygen levels), while UV rays are an external factor that triggers the action of wearing sunglasses.

Answer:

B. wearing sunglasses to protect eyes from UV rays