Urushiol is a potent allergen from poison oak that can cause an immune response in susceptible individuals. What is the primary purpose of desensitization to poison oak?

• A. To treat the allergen as one of the body's natural enzymes.
• B. To produce antigen out from the allergen.
• C. To restrict the immune system from responding.
• D. To induce tolerance against the allergen.

Answer: (D)