A Researcher Is Testing the Notion That Viewing a Popular

A researcher is testing the notion that viewing a popular children's show is associated with brief cognitive deficits. She selects a sample of 75 4-year-old boys. Each boy is randomly assigned to one of three groups. In Group A, the boys watch an 8-minute clip of a television show popular with children. In Group B, the boys watch 8 minutes of an educational show. In Group C, the boys draw and color for 8 minutes. Each boy takes part alone and is unaware that other children are participating. After the 8-minute session, a research assistant assesses each boy's performance on a cognitive task. The assistant was not present during the 8-minute session and does not know which group any of the boys is in. Identify the elements of this experiment corresponding to each of the following concepts: experimental group; control group; independent variable; dependent variable; placebo; control; and double-blind study.