How Can Streptococcus Pyogenes Initially Be Differentiated from Other Streptococcus Species

How can Streptococcus pyogenes initially be differentiated from other Streptococcus species that form part of the throat normal microbiotia?

A) By Gram staining-it is a Gram-positive organism.
B) By culturing the bacteria on nutrient agar and checking for hemolysis.
C) By morphology-the bacteria are spherical and grow in long chains.
D) By detection of the "A" carbohydrate in its cell wall using antibodies.
E) By specific disease signs and symptoms, including sore throat and fever.