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: Anatomy
All the following species of Haemophillus show satellitism , except 
Select and explain. 
A. H. influenzae, B. H.aegypticus, C. H.haemolyticus, D. H.ducreyi
D: H.ducreyi
Answer: D: H.ducreyi 
Explanation: Satellitism is seen when the organism lacks factor V that is provided by S.aureus. But H.ducreyi is needs only factor X for growth. Hence it does not show satellitism.