Dr johnannasen is psychologist whose research is based on that of mamie phipps clark, the first black women to be awarded a phd in psychology. dr johanssens research would likely focus on:

Which of the following  bestillustrates a negative reinforcer?               a.  copland gives up candy to stave off chronic acid indigestion.    b.  nancy learns that she prefers chocolate over vanilla.    c.  carmine changes his major to english lit after failing a math exam.    d.  on a hot day, lindberg always drinks lemonade.