The textbook describes a study (lillard & peterson, 2011) in which children were randomly assigned to one of three 9-minute activity conditions: watching spongebob squarepants, watching an educational program, or drawing and coloring. all the children's performance on cognitive tasks was then assessed. because the children were randomly assigned to conditions, this study is an example of research.

experimental

Explanation:

The textbook describes a study (Lillard & Peterson, 2011) in which children were randomly assigned to one of three 9-minute activity conditions: watching SpongeBob SquarePants, watching an educational program, or drawing and coloring. All the children's performance on cognitive tasks was then assessed. Because the children were randomly assigned to conditions, this study is an example of experimental research.

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