Professor Smith has been studying the development of moral reasoning in a group of people over the last 30 years.The participants were all 1 year old when she began her study.Professor Smith,who intends to hand off her study to a younger researcher in the department after she retires next year,is conducting a

A) factor analysis.
B) longitudinal study.
C) cross-sectional study.
D) test standardization.

A longitudinal study is a type of research design where data is gathered from participants over an extended period of time, often years or even decades. In this case, Professor Smith has been studying the development of moral reasoning in a group of people for 30 years. This type of study allows for the examination of changes in behavior or development over time and is often used in developmental or medical research. The other choices, factor analysis, cross-sectional study, and test standardization, do not accurately describe Professor Smith's research design.