It has been rumored that campus parking enforcement officers receive a $10 bonus for every twenty tickets they write. An unnamed campus parking administrator has remarked off the record, "This schedule of reinforcement keeps our officers diligent and busy."A) variable-ratio
B) fixed-ratio
C) variable-interval
D) fixed-interval

B. Fixed ratio

Explanation:

Fixed ratio schedule is a type of schedule reinforcement where response is reinforced after only a specific number of response. In this case, a response of $10 bonus is reinforced after only they write twenty (20) tickets (specific number of response).

They are those in which a response is reinforced only after a specified number of responses. The idea is that, the worker produces a agreed upon number of responses with the manager or owners. And when he reaches that number of responses, he's offered his reward in bonuses.