**Core Concept**
Systematic desensitization is a behavioral therapy technique used to treat anxiety disorders, such as phobias. It involves gradually exposing the patient to the feared object or situation in a controlled and hierarchical manner, with the goal of reducing anxiety and increasing tolerance.

**Why the Correct Answer is Right**
The process of systematic desensitization involves creating a hierarchy of anxiety-provoking stimuli, starting from the mildest to the most intense. The patient is then gradually exposed to each item on the hierarchy, with the goal of reducing anxiety through relaxation techniques, such as deep breathing or progressive muscle relaxation. This allows the patient to become desensitized to the feared object or situation, reducing anxiety and improving coping mechanisms. The therapist typically uses a systematic approach, starting with small steps and gradually increasing the intensity of the exposure.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because systematic desensitization is a specific type of behavioral therapy, whereas cognitive-behavioral therapy (CBT) is a broader category of therapy that encompasses various techniques, including systematic desensitization.
**Option B:** This option is incorrect because aversion therapy involves associating an unpleasant stimulus with the feared object or situation, whereas systematic desensitization involves gradual exposure to the feared stimulus in a controlled manner.
**Option C:** This option is incorrect because flooding involves rapid and intense exposure to the feared object or situation, which can be counterproductive and even traumatic, whereas systematic desensitization involves gradual and controlled exposure.

**Clinical Pearl / High-Yield Fact**
Systematic desensitization is often used in combination with other behavioral therapies, such as CBT, to treat anxiety disorders. It is essential to create a personalized hierarchy of anxiety-provoking stimuli that is tailored to the patient's specific needs and fears.

**Correct Answer: B. Aversion therapy involves associating an unpleasant stimulus with the feared object or situation.