Final answer:
The sociological theory that views population growth as a normal and essential process for society is functionalism (option D).
Step-by-step explanation:
The sociological theory that considers population growth and its various components as normal and essential processes for society is D. functionalism. Functionalism views society as a complex system whose parts work together to promote solidarity and stability. This perspective sees population growth as a necessary and integral component for the continuation and functioning of a society.
For example, functionalists might research how emigration and immigration strengthen ties between nations or how the division of labor leads to gender inequality, which in turn is seen as a means to maintain family stability and cohesion.