Answer:
Ten year old boys
Explanation:
Cross sectional research design are usually used to understand the dominant character or features in a population at a particular point in time. Some of the characteristics of a this study design are; takes place at one time, allows researchers to compare certain characteristics such as age, can provide information about what is happening with a certain population and what is happening in another population say 5 years later, and then use this information as a basis of comparison. Researchers do not use this study to show cause-and-effect, but it is used mainly for correlational analysis.
