Microbiology Immunology 0438a918 Immunoglobulin which is produced first by the fetus in response to infection:(1987) A IgG B IgA C IgM D IgD High-Yield Explanation Ans: c (IgM)Ref: Ananthanarayan Micro, 7thed, p. 89 & 6th ed, p. 83, 84