Which of the following types of vaccines involves the use of a weakened form of the pathogen?

Explanation: Recognizing and responding to specific antigens. T cells are a type of lymphocyte that plays a central role in cell-mediated immunity. They recognize and respond to specific antigens presented by infected or abnormal cells, leading to their destruction.

Incorrect choices:

a. T cells are not responsible for the production of antibodies, but that is the role of B cells in the humoral immune response.

b. While T cells are involved in directly attacking and destroying infected cells, their main function is to recognize specific antigens rather than directly attacking pathogens.

c. Marking pathogens for destruction by phagocytes is primarily a function of antibodies and complement proteins, not T cells.

Explanation: Celiac disease is an autoimmune disorder in which the immune system attacks and damages the lining of the small intestine in response to the ingestion of gluten, a protein found in wheat, barley, and rye.

Incorrect choices:
a. Rheumatoid arthritis primarily affects the joints, not the small intestine.
b. Sjögren's syndrome primarily affects the salivary and lacrimal glands, not the small intestine.
d. Type 1 diabetes mellitus is an autoimmune disorder in which the immune system attacks and destroys insulin-producing beta cells in the pancreas, not the small intestine.