The correct answer is A. C5-9.

This is a photo of disseminated gonococcemia, which can be associated with a deficiency of C5-9. This deficiency increases susceptibility to Neisseria.

C3 and C4 are decreased in active systemic lupus erythematosus, especially when the kidneys are involved. They can also be decreased in hypocomplementemic urticarial vasculitis.
Decreased IgM is associated with Wiskott–Aldrich.
Leukocyte adhesion 1 deficiency is associated with a B2-integrin deficiency.
Bruton’s agammaglobulinemia is associated with a decrease in immunoglobulin due to decreased mature B cells.

References:

Janeway et al. Immunobiology 5. New York: Garland Publishing, 2001.

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