The Mueller-Hinton medium used in the Kirby-Bauer assay contains no para-aminobenzoic acid (PABA, normally found in most media) because it

A) causes an increase in bacterial lag time.
B) interferes with the diffusion of penicillin and penicillin-like drugs.
C) creates a false bacteriostatic effect.
D) polymerizes streptomycin drugs and their derivatives.
E) inhibits sulfa antibiotics testing.