Streptococcus - Medical Science

Q1:

Crystal violet blood agar is a selective medium for

A β-haemolytic streptococci

B Staphylococcus aureus

C Corynebacterium diphtheriae

D Mycobacterium tuberculosis

ANS:A - β-haemolytic streptococci

This is because other species of Streptococcus species and other gram positive organism are inhibited by sodium chloride.