This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Introduction and gametogenesis., Subject name: Anatomy
[{'content': 'During spermatogenesis, chromosome no. reduces to haploid at:- \nSelect and explain. \nA. At mitosis, B. Meiosis -I, C. Meiosis-II, D. None of above', 'role': 'user'}, {'content': 'Answer: B \nExplanation: The first meiotic division is known as the reduction division in which each primary spermatocyte yields two secondary spermatoctyes. Each contains 23 (Haploid) chromosomes consist of two varieties 22+X and 22+Y. Here 22 are autosomes and X & Y are sex chromosomes.', 'role': 'assistant'}]