This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
Chemotactic complement component are 
Select and explain. 
A. C3a, B. C5a, C. Both, D. C3b
B: C5a
Answer: B: C5a 
Explanation: ref Robbins 8/e p64 ;7/ep56;9/e p77.