This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Infertility, Subject name: Gynaecology & Obstetrics
In the perspective of the busy life schedule in the modern society, the accepted minimum period of sexual co-habitation resulting in no offspring for a couple to be declared as infeile is: 
Select and explain. 
A. One year, B. One and a half year, C. Two years, D. Three years
A: One year
Answer: A: One year 
Explanation: Infeility is defined as a failure to conceive within one year of regular unprotected coitus. Primary Infeilty denotes those patients who have never conceived. Seconday Infeility indicates previous pregnancy but failure to conceive subsequently. Reference- DC Dutta's Textbook of gynaecology 7th edition page no.186