Which best describes the age structure of a population with zero population growth?
question 5 options:

the majority of people are of prereproductive ages in a broad-base pyramid age structure diagram.

the age-structure diagram would be narrow at the bottom and top with a broader middle.

the age structure would be broad at the top in postreproductive ages and narrow downward in an inverted pyramid.

the age-structure diagram would be column-shaped with all age classes approximately equal.

The correct option is D) The age-structure diagram would be column-shaped with all age classes approximately equal.

Explanation:

A zero population growth can be described as a scenario in which the number of birth rates equals to the number of death rates in an area. Social workers think that for an economy to become stable, zero population growth shall be achieved.

The age structure of a zero population growth can be depicted by column shape which are equal for all age classes because the number of birth and the death rates will be equal. Hence, the number of each age will also be equal.

answer: - b cells

explanation: -

so, the b cells mediate their action by identifying the antigens present on the surface of the pathogens and then producing antibodies in return to mediate its effect.