The total fertility rate in a economy is defined as :

1. A

   the number of children born per 1000 people in the population in a year.

   Children per 1,000 people in a year. That is a crude birth rate, not TFR.

2. B

   the number of children born to couple in their lifetime in a given population.

   Children born to a couple in their lifetime. TFR is per woman, not per couple.

3. C

   the birth rate minus death rate.

   Birth rate minus death rate. That is natural increase.

4. D

   the average number of live births a woman would have by the end of her child- bearing age.

   Average live births a woman would have by the end of child-bearing, given current age-specific rates.

Summary. Official key is (d). Total fertility rate is the average number of live births a woman would have over her reproductive life if current age-specific fertility rates held. It is not CBR, not “per couple”, and not birth minus death.