Which defense mechanism involves switching unacceptable impulses into their opposites?

The concept of switching unacceptable impulses into their opposites is known as reaction formation. This defense mechanism occurs when an individual feels an urge or impulse that they find to be unacceptable, and instead of acting on that impulse, they exhibit behavior that is directly contrary to it. For example, a person who harbors feelings of anger or aggression toward someone may go out of their way to show kindness or friendliness to that person instead. This helps them to cope with their internal conflicts by expressing the opposite of what they truly feel, thereby reducing anxiety related to those feelings.

In the context of the other choices, displacement refers to redirecting an emotion or impulse from its original target to a more acceptable one, rather than creating an opposing behavior. Rationalization involves creating excuses to justify behaviors or feelings, rather than transforming them into the opposite. Sublimation allows unacceptable impulses to be expressed through socially acceptable activities, such as channeling aggressive impulses into sports. Reaction formation, however, uniquely emphasizes the transformation of an impulse into its direct opposite, making it the correct answer in this scenario.