Answer:
A. Birth rate.
Step-by-step explanation:
The bir th rate refers to the ratio of the number of live -born bir ths per year. In other words, it is the number of people or animals, or living beings born per year.
To measure the number of children born in a country, the best rate measure will be the bir th rate. This will provide the number(s) of babies born in that particular place in a year.
Thus, the correct answer is option A.