Final answer:
The correct option is c. Type IV hypersensitivity is a T-cell-mediated hypersensitivity reaction that does not involve antibodies. An example of Type IV hypersensitivity is contact dermatitis caused by exposure to poison ivy.
Step-by-step explanation:
Type IV hypersensitivity is a T-cell-mediated hypersensitivity reaction that does not involve antibodies. It is regulated by T cells and involves the action of effector cells. One example of Type IV hypersensitivity is contact dermatitis caused by exposure to poison ivy.
In this case, the body becomes sensitized to the hapten antigens present in poison ivy, leading to a delayed hypersensitivity reaction upon subsequent exposure.