The number of children born per 1000 people in the population in a year. This describes the crude birth rate, not the total fertility rate.

The number of children born to a couple in their lifetime in a given population. This is close but not quite accurate. The total fertility rate is calculated for women, not couples.

The birth rate minus death rate. This defines the rate of natural increase, which indicates population growth, not fertility.

The average number of live births a woman would have by the end of her child-bearing age. This is the correct definition of Total Fertility Rate (TFR). It's a hypothetical measure assuming a woman lives through her childbearing years and experiences the age-specific fertility rates of a given period.

In simple terms, TFR tells us the average number of children a woman would have if current birth trends continued.