A(n) reinforcer refers to the removal of an unpleasant stimulus, putting on a sweater when you're cold for example, which leads to an increase in the probabilitythat a preceding response will be repeated in the future.

The correct answer is negative

Explanation: Negative reinforcement is a term described by BF Skinner operant conditioning theory. In negative reinforcement, a response or behavior is reinforced by stopping, removing or avoiding a negative result or aversive stimulus.

Aversive stimuli tend to involve some kind of discomfort, whether physical or psychological. Behaviors are negatively reinforced when they allow you to escape aversive stimuli that are already present or allow you to avoid aversive stimuli completely before they happen.

People are mean sometimes because people around them are mean or they just don't know how to make friends sometimes so they just bully them.

Explanation:

But please ignore them,because they really don't mean what they're saying.Dont let them tell you you're not beautiful because everyone is beautiful in there own way.