Choose one best prenatal, infancy, toddlerhood, preschool age, middle childhood, adolescence, young adulthood, middle adulthood and late adulthood
a. are universal stages of human development that are marked by distinct biological changes.
b. are social constructions only, and as such, they cannot be used for scientific purposes.
c. are acceptable markers of developmental changes; however, their timing and even the existence of some of the life stages can still be questionable. for example, people mature at different rate and some periods don't have clear biological markers.
d. are mostly social constructs of western culture. many non-western cultures have adopted a different set of human developmental stages

C. are acceptable markers of developmental changes; However, their timing and even the existence of some of the life stages can still be questionable. For example, people mature at different rate and some periods don't have clear biological markers.

Explanation:

Psychologists try to understand child development by dividing the age of a child into stages. There are many theories that try to understand human psychology by dividing the age into stages. These theories are known as Developmental stage theories.

The stages of life have been defined by psychologists by observing children and coming to a conclusion that what age falls into what stage of development. The stages have been divided by the patterns which are seen among the majority of childres. But, there are some people who do not follow this pattern due to some psychological or biological reasons.

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