What is an Antigen and Antibody?
No plagiarism plz.

Explanation:

Antigens are molecules capable of stimulating an immune response. Each antigen has distinct surface features, or epitopes, resulting in specific responses. Antibodies (immunoglobins) are Y-shaped proteins produced by B cells of the immune system in response to exposure to antigens.

Antibodies are proteins made by the immune system to fight infections like viruses and may help to ward off future occurrences by those same infections. Antibodies can take days or weeks to develop in the body following exposure to a virus infection and it is unknown how long they stay in the blood.

Explanation:

Antigen is a toxin or other foreign substance which induces an immune response in the body, especially the production of antibodies.

i believe the answer would be b. hope it : )