An infant boy experiences multiple bacterial, viral, and fungal infections during his first year of life. He has also been suffering diarrhea since birth. Tests are performed to determine the likely cause of his symptoms. Serum calcium levels are normal,
7
votes
A. Defective interleukin-2 receptors
B. Failure of the third and fourth pharyngeal pouches to descend
C. Inability of helper T lymphocytes to switch classes
D. Lack of NADPH oxidase activity
E. X-linked tyrosine kinase defect