This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteriology, Subject name: Microbiology
A pus culture on chocolate agar shows gram-negative cocci most likely organism is 
Select and explain. 
A. Hemophilus ducreyi, B. Nisseria gonorrhoeae, C. Streptococcus pyogenes, D. Streptococcus pneumoniae
B: Nisseria gonorrhoeae
Answer: B: Nisseria gonorrhoeae 
Explanation: Streptococcus pneumoniae and Streptococcus pyogenes are gram-positive cocci. Hemophilus ducreyi is ovoid bacilli. It is gram negative but may appear gram-positive and frequently show bipolar staining. Gonococci is a gram-negative coccus. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 236