A 2 year old boy was healthy for the first six months of life. He then develops recurrent infections. Serum concentration of complement, phagocytic function and bactericidal function of neutrophils are normal. A skin test with Candida antigens shows 2 cm of induration at 48 hours.
The time of onset of the disease is best explained by:
A. development of a viral infection.
B. exposure to rare bacteria.
C. a maturation defect in the thymus.
D. transplacental transfer of IgM antibodies.
E. loss of passive immunity from the mother

iamback032018 Asked question July 20, 2021