A) Strongly pigmented S. aureus on Mueller-Hinton agar, incubated for 24 h at 37°C

B) S. aureus (large, yellow pigmented) vs. nonpigmented streptococci (S.equi ssp. zooepidemicus)

C) S.aureus (yellow pigmented) vs. nonpigmented S. epidermidis

D) S.aureus colonies without yellow pigment