What proportion of 3-year-old American children receive less than the recommended amount of calcium?

Correlational research designs are NOT appropriate for purposes of _______________

A) causation B) description C) prediction D) describing relationships

In regard to adolescent roles,

A) adolescents may "try on" various roles, experiment with those roles, and make decisions to adopt some roles and reject other roles. B) there is little change until adulthood. C) adolescents reject most predetermined social roles. D) adolescents' new roles are the root of most behavioral problems.