Shelby and her friends love to play freeze tag. They almost always play by standard rules, but they do discuss rules with play according to this shared knowledge

What are the common problems encountered by those who wish to conduct research on the validity of police screening?

A. Applicants try to present themselves in a positive light. B. Applicants who do poorly on screening evaluations are eliminated from the pool of applicants so one cannot evaluate whether predictions of poor performance would have been valid. C. Testing actual police performance on the field is time-consuming and expensive. D. All of these are correct.

As children undergo the cognitive developments of middle childhood, their self-concepts focus exclusively on concrete external traits, such as appearance, activities, and living situations.

Answer the following statement true (T) or false (F)