Memory Cells Enable Rapid Secondary Immune Response

Steps:

• Memory cells form after initial antigen exposure and persist long-term.
• Upon re-exposure, they quickly differentiate into effector cells for faster immunity.
• They ensure stronger, quicker antibody production than primary response.
• Evaluate statements: 1 (correct: long-term persistence), 2 (incorrect: plasma cells produce antibodies), 3 (incorrect: not sole role), 4 (correct: rapid activation).

Why B is correct:

• B selects 1 and 4, matching memory cells' defined role in persisting and enabling swift secondary responses per immunology principles.

Why the others are wrong:

• A includes incorrect 2 and 3, overstating antibody production and roles.
• C omits valid 4, missing rapid response aspect.
• D includes wrong 2, misattributing antibody production to memory cells.

Not enough information on exact statements 1-4 for full verification.

Final answer: B