A researcher is studying how depression tends to be experienced by people of different ages. The researcher interviews depressed adolescents, young adults, individuals in their 30s and 50s, and those over 70 years old. The research design being used is called cross-sectional.
Option: D
Explanation:
A kind of design for observational study is understood as a cross-sectional framework. In a cross-sectional analysis the investigator simultaneously tests the participants in the study's result and exposures. Through cross sectional studies one can estimate the prevalence of disease.
A cross-sectional analysis, for instance, could be used to assess whether vulnerability to specific risk factors would correlate with specific outcomes. For illustration, a researcher may gather cross-sectional data about past smoking habits and current lung cancer diagnoses.