Group B Beta-hemolytic streptococci are differentiated by other streptococcus groups by using.. Bacitracin sensitivity disc

Group B Beta-hemolytic streptococci are differentiated by other streptococcus groups by using:
a- Optochin
b- Neufeld Quelling reaction.
c- Niacin test
d- Catalase test.
e- Bacitracin sensitivity disc***