UKMLA PLAB AMC USMLE Prometric MCQ

Question Number 0948
Question:
A 25 year old female with systemic lupus erythematosus has repeated sinus infections and respiratory infections. She is told that she has a specific immunoglobulin deficiency. Which immunoglobulin is most likely deficient?

a) IgD
b) IgA
c) IgE
d) IgG
e) IgM