Impetigo Can Be Caused by Either Staphylococcus Aureus or Streptococcus

Impetigo can be caused by either Staphylococcus aureus or Streptococcus pyogenes.Culture-based identification of the causative organism can be complicated by

A) the common surface antigens of these two organisms.
B) the ability of S.aureus to kill S.pyogenes.
C) the fastidious nature of both organisms.
D) their common optimal growth temperature, 37°C.