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
A feilized ovum reaches uterine cavity in? 
Select and explain. 
A. 3-4 days, B. 5-6 days, C. 7-8 days, D. 10 days
A: 3-4 days
Answer: A: 3-4 days 
Explanation: 3-4 days REF: William's obstetrics 22nd ed, Langman's Medical Embryology 9' edition page 45 LH Surge 24 hours before ovulation Ovulation 0 hours Feilization 24 hours after ovulation (Day 1) Reaches uterine cavity 3-4 days post feilization (Day 4-5 post ovulation) Implantation 7-9 day post feilization