Answer:
Option (4).
Step-by-step explanation:
The exaggerated or hyper active response of the immune system are responsible for the hypersensitive reactions. These reactions are harmful for the body.
Delayed hypersensitivities or Type IV hypersensitivities is mediated by T cells. The T cells attacks the self protein complex and causes the allergic contact dermatitis.
Thus, the correct answer is option (B).