Question

what causes tuberculosis?
a bacterial infection
a viral infection
an antigen

Explanation:

Tuberculosis (TB) is caused by bacteria. The bacteria that cause TB is Mycobacterium tuberculosis. It is a bacterial infection. Viral infections are caused by viruses (e.g., common cold by rhinovirus). An antigen is a substance that can trigger an immune response, not a cause of an infection like TB.

Answer:

A. A bacterial infection