Question

Susan complains that she is in an "addictive love relationship" in which she has to work very hard to get her partner to pay any attention to her. chances are that her partner is reinforcing her on a ____ schedule.

Answer 1

I believe the answer is: Variable ratio
In a variable ratio schedule, a certain schedule is made for reinforcement  where a response is reinforced after an unpredictable number of responses. Due to constant expectation created from the unpredictability, this type of schedule usually has a high rate of responding.