is in exocrine gland secretions (breast milk, saliva, tears) and defends against bacteria and viruses. is found in plasma and activates complement and reacts with blood cells during transfusions.

Explanation:

IgA is the chief antibody which is secreted at mucosal surface of various tissues. They basically provide the first line of defense in our body immune system.

IgM is the antibody that are found in the blood and lymph. They come into scene when the body encounters a new type of infection. So they are produced is large quantity in order to capture these antigens & flush them out of our body.

b.

hoped i

explanation:

c is the answer to this question. altitude affects the weather because air molecules evaporate.