Which of the following research methods is most likely to demonstrate causal relationships between variables?

Brian is in the fourth grade. Brian does well in school and he loves to play soccer. However,

most of the children in his class will not play with him because he never passes the ball and often knocks them down. He has displayed these behaviors for the past year. Which one of the following conditions is Brian likely exhibiting? a. Attention-deficit, hyperactive/impulsive type b. Attention-deficit, inattentive type c. Childhood-onset conduct disorder d. Obsessive compulsive disorder

When Sadie says, "I goed to the store," her mother replies, "Yes, you went to the store." Sadie's mother's response is an example of

A) fast-mapping. B) a recast. C) an overregularization. D) an expansion.