A patient develops a skin rash characterized by erythema and vesicles 48-72 hours after exposure to poison ivy. Which type of hypersensitivity reaction is responsible for this clinical presentation?

✓ Correct Answer: Option D

The reaction to poison ivy is a classic example of Type IV (delayed-type) hypersensitivity. It is cell-mediated, involving T-lymphocytes and macrophages, with symptoms typically appearing 24-72 hours post-exposure.