Question

multiple choice question
antibodies are secreted by ______.
plasma cells
red blood cells
platelets

Explanation:

To solve this, we recall biological concepts: Antibodies are proteins involved in the immune response. Plasma cells (a type of B - cell) are responsible for secreting antibodies. Red blood cells carry oxygen, and platelets are involved in blood clotting, so they don't secrete antibodies.

Answer:

A. plasma cells