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: Physiology
The acrosome reaction occurs, when the sperm 
Select and explain. 
A. Enters the uterine cavity, B. Comes in contact with zona pellucida, C. Penetrates corona radiata, D. Penetrates cell membrane of oocyte
B: Comes in contact with zona pellucida
Answer: B: Comes in contact with zona pellucida 
Explanation: None