Question

Select the incorrectly matched pair(s).

	Column I	Column II
1.	Birth rate	Ratio of number of individuals added (by births) in a population in a given amount of time to the initial population
2.	Death rate	Ratio of number of individuals died in a population in a given amount of time to the initial population
3.	Sex ratio	Ratio of reproductive to post-reproductive individuals in a population
4.	Age pyramid	Pyramid obtained when the percent individuals of a given age or age group is plotted for the population

• A. 2 only
• B. 1 and 4 only
• C. 1 and 2 only
• D. 3 only

Answer 1

The correct option is D 3 only

Birth rate, death rate and sex ratio are certain attributes of a population.

Birth rate: it can be defined as the ratio between the number of individuals born in an existing population and the initial population size, in a given time period.

Death rate: it can be defined as the ratio between the number of individuals died and the initial population size, in a given time period.

Sex ratio: an individual can be biologically born as a male or female. Based on the sex of the child, the population can be divided into male population and female population. But the ratio of male to female population in a region is called sex ratio. It is one of the important attributes calculated under the human population census.

Age pyramid: pyramid obtained when the percent individuals of a given age or age group is plotted for the population. A population at any given point of time is composed of individuals of different ages. For ease, individuals are divided into different age groups (pre-reproductive, reproductive and post-reproductive age groups).

Therefore, 3 is the incorrectly matched pair.