Susan learned at a young age that developing good study habits, such as doing her homework, brought about good grades, and this made her want to work harder in school. This type of behavior is being strengthened through .

Reinforcement

Explanation:

Reinforcement is the process through which any behavior, act or other aspect is increased or strengthened for generation of response in terms of operant conditioning.

According to the question,Susan is indulged in reinforcement through which her behavior is getting strengthened.She is learning good habits of studying, doing homework , hard work etc at early age so that it will help her getting good marks.

the right answer is a