which portion of the lymphatic system is the major site of antibody production?

The answer is spleen

Spleen is organ that has a role in red blood cells and the immune system. The spleen is connected to the lymph vessel. Spleen produce antibodies and destroy pathogen or any cells that binds with the antibodies. Adaptive antibody would be produced by plasma cell which come from B-cell.

in a chemical reaction, the atoms and molecules produced by the reaction are called products. no new atoms are created, and no atoms are destroyed. in a chemical reaction, reactants contact each other, bonds between atoms in the reactants are broken, and atoms rearrange and form new bonds to make the products.