【单选题】In an evaluation of an 8-year-old who has recurrent infections since the first year of life, findings include enlargement of the liver and spleen, lymph nod inflammation, and a superficial dematitis r...
A.
Defect in the enzyme NADPH oxidase
B.
Defect in the enzyme adenosine deaminase ( ADA )
C.
Defect in the IL-2 receptor
D.
Developmental defect at the pre-B stage
E.
Developmental failure of pharyngeal pouches 3 to 4