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: Anatomy
Secondary Oocyte is : 
Select and explain. 
A. n and N, B. n and 2N, C. 2n and N, D. 2n and 2N
B: n and 2N
Answer: B: n and 2N 
Explanation: Primary Oocyte – 2n.
Secondary Oocyte – n and 2N.
Spermatid – n and N.