Dorothy did her science homework regularly and studied long hours for tests. even so, she continued to get poor grades. over time, she decreased her efforts in doing homework and studying. eventually she failed science. the behavioral perspective would suggest that dorothy's poor grades are an example of

The poor grades here is an example of Punishment.
In social behavioral field, punishment refers to the negative outcome that are considered undesirable by an individual.
The poor grade in this context is caused by Dorothy failing to give her best effort in her study due to her false response in identifying the cause of her previous failure.