Answer:
cross-sectional
Explanation:
Cross-sectional studies are used to measure the exposure and outcome of a population or study group at a specific point of time. It is used in different fields including developmental psychology, social science, and education, based on the interest area of research. It is an observational method of research because researcher cannot manipulate the variables in this type of research.
D is the answer Have a nice day
Because they probably don't know all the mean and hurtful things people can say or do. OR they haven't seen the things of this field so they don't have to worry and cry because maybe they don't have huge muscles like some guy they saw in a magazine.