Microbiology – MCQ 29 – Infant with high grade fever and respiratory distress

An infant had high grade fever and respiratory distress at the time of presentation to the emergency room. The sample collected for blood culture was subsequently positive showing growth of a haemolytic colonies. On Gram staining these were gram positive cocci. In the screening test for identification, the suspected pathogen is likely to be susceptible to the following agent:
a) Bacitracin
b) Novobiocin
c) Optochin
d) Oxacillin

Correct answer : c) Optochin