Which is an example of an internal stimulus? a. a sudden change of air temperature b. an artificial light that attracts insects c. an increase in the amount of water available to a plant d. a decrease in oxygen levels in the blood during exercise

The answer i got was this. This is for student from k12

Explanation:

out of the choices i'd say d the ability to set goals, mainly because to desire to continue you need motivation but it isn't motivation in that part, but setting goals means you have an endgame and you want to reach it which sums up motivation.