Professor Jones is studying how a person responds to the temptation to violate moral rules, such as lying and cheating. Professor Jones is studying which aspect of moral development?

Behavioral

Explanation:

In psychology, moral development has to do with the understanding of morality that takes place since childhood and until adulthood. According to different models, we go through different stages in our moral development as we grow older.

However, moral development has two different aspects:

Cognitive: Has to do with our thoughts and beliefs about things and their morality. Behavioral: Has to do with our actions regarding rules and morality, it's the way we act in moral dilemmas.

In this example, Professor Jones is studying how a person responds to the temptation to violate moral rules such as lying and cheating, we can see that both lying and cheating refer to behaviors, therefore, he is focusing on the behavioral aspect of moral development.