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: Unknown
To achieve a net reproduction rate (NRR) of 1, the couple protection rate (CPR) should be: 
Select and explain. 
A. 20%, B. 30%, C. 40%, D. 60%
D: 60%
Answer: D: 60% 
Explanation: Ref. Foundations of Community medicine. Page. 113
 
Couple Protection Rate (CPR)
• It is an indicator of the prevalence of contraceptive practice in the community
• Definition: the percentage of eligible couples effectively protected against childbirth by one or the other approved methods of family planning
– Sterilization
– IUD
– Condom
– OCP’s
• NRR = 1 can be achieved only if the CPR > 60%