This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Pathology of Conception, Subject name: Gynaecology & Obstetrics
In the perspective of the busy life schedule in the modem society, the accepted minimum period of sexual cohabitation resulting in no offspring for a couple to be declared infertile is: 
Select and explain. 
A. One year, B. One and a half-year, C. Two years, D. Three year
A: One year
Answer: A: One year 
Explanation: Ans. is 'a' i.e., One year If a couple fails to achieve pregnancy after one year of "unprotected' and regular intercourse, it is an indication to investigate the couple