Question

extrinsic motivation involves doing academic tasks for external
achievement
knowledge
reward.
goals.

Explanation:

Extrinsic motivation is driven by external factors. A reward is an external factor that can prompt one to do academic tasks. Achievement can be internal - a sense of personal accomplishment. Knowledge acquisition is often an internal - focused goal. Goals can be either internal or external, but reward is the most typical external factor here.

Answer:

C. reward