Marc never does his homework. his mother begins reinforcing him with additional "screen time" whenever he simply sits at his desk after dinner. after a week, she reinforces him only when he opens his books and assignments. one week later, she reinforces him only when he completes at least a portion of his assigned homework. marc's mother is using: a. shapingb. secondary reinforcementc. higher order conditioningd. stimulus discrimination

A). Shaping.

Explanation:

As per the given description of Marc's behavior and his mother's attitude to amend his habits exemplify that his mother is employing 'shaping' as it would establish his behavior which was previously not performed. This concept was first defined by B.F. Skinner who was a leading psychologist advocating 'behaviorism'. 'Shaping' is quite commonly employed by teachers and mothers to inculcate or reinforce certain behavior in kids that would help them to perform better and reach nearer to their targets. Similarly, Marc's mother is reinforcing 'successive approximations' to instill a behavioral change in him and attain the desired goal(when Marc begins to do his homework regularly). Thus, option A is the correct answer.

is this multiple choice?