A longitudinal study is one in which

A) individuals of different ages are compared with one another.
B) the behavior of a large group is assessed by different researchers.
C) development is studied during an unspecified period.
D) the same people are retested over a long period.

Longitudinal Study

A research design that involves repeated observations of the same variables over short or long periods of time to detect changes or developments.

Retested

The process of being tested again to verify results or check for changes over time.

Different Ages

Refers to the variety in the chronological ages of individuals within a population, highlighting diversity in stages of life.