Step 1: Understanding the Concept:
The question asks to identify a specific type of therapy whose primary goal is to identify, challenge, and change irrational beliefs.
Step 2: Detailed Explanation:
(A) Cognitive Behavior Therapy (CBT): This is a broad category of therapies that focus on the interplay between thoughts, feelings, and behaviors. While it does address irrational thinking, one of the other options is more specific and foundational to this idea.
(B) Behavior Therapy: This focuses on changing maladaptive behaviors using principles of learning (classical and operant conditioning), without a primary focus on internal thoughts or beliefs.
(C) Rational-Emotive Therapy (RET), now Rational Emotive Behavior Therapy (REBT): Developed by Albert Ellis, this is a pioneering form of cognitive therapy. Its central thesis is that emotional and behavioral problems are the result of irrational beliefs. The therapist's role is to be highly directive, actively disputing these irrational "shoulds," "musts," and "oughts" to help the client adopt a more rational and logical philosophy of life. This is a perfect match for the question's description.
(D) Psychodynamic Therapy: This therapy focuses on exploring unconscious conflicts and early life experiences to gain insight into a person's current problems.
Step 3: Final Answer:
Rational-Emotive Therapy is the specific approach that focuses on persuading individuals to change their underlying irrational assumptions.