This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Microbiology
C-3 convease in alternate complement pathway ? 
Select and explain. 
A. C4b2a, B. C3b, C. C3bBb, D. C3a
C: C3bBb
Answer: C: C3bBb 
Explanation: Ans. is 'c' i.e., C3bBb . The central process in the complement cascade (both in classical and alternative pathway) is the activation of C3 by C3-convease. . In classical pathway C3-convease is C4b2a and in alternative pathway C3-convease is C3bBb.