How do demographers measure the rate at which a population is growing?
a. by adding the birth rate to the infant mortality rate
b. by subtracting the infant mortality rate from the birth rate
c. by comparing the birth and death rates
d. by counting the number of people in a given area

Demographers measure the rate at which a population is growing by comparing the birth and death rates. The correct option among all the options given in the question is option "C". By deducting the number of birth rates with the number of death rates, the demographers can easily come to know whether the population is increasing or decreasing.