This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Immunology, Subject name: Microbiology
[{'content': 'Contact dermatitis is - \nSelect and explain. \nA. Type-I hypersensitivity, B. Type-II hypersensitivity, C. Type-III hypersensitivity, D. Type-IV hypersensitivity', 'role': 'user'}, {'content': "Answer: D \nExplanation: Contact dermatitis is a type IV hypersensitivity reaction. - delayed hypersensitivity sometimes results results from skin contact with a variety of chemicals - metals such as nickel and chromium, simple chemicals like dyes,drugs or plant allergens. The antigen activates specifically sensitised CD4 & CD8 T lymphocytes leading to the secretion of lymphokines and phagocyte accumulation. Reference : Anathanarayan & paniker's 9th edition, pg no: 162,167 <\\p>", 'role': 'assistant'}]