Question

a total fertility rate of 2.1 is known as select one: a. replacement fertility. b. negative fertility. c. demography. d. age distribution.

Explanation:

Replacement fertility is the total fertility rate at which women give birth to enough babies to sustain population levels. A rate of 2.1 is commonly considered replacement fertility as it accounts for mortality and other factors to keep the population stable over time. Negative fertility is not a standard term related to this value. Demography is the study of populations in general, and age - distribution refers to the proportion of different age - groups in a population.

Answer:

A. replacement fertility.