Answer:
naturalistic observation
Explanation:
Naturalistic observation refers to the type of research that conducted by observing the subjects' uncontrolled behavior when they are in their natural environment.
If the professor want to observe how children develop their social and intellectual skills, the school classroom is considered as the perfect natural environment because in this place children will show how they gather around the people that they like and form a close friendship with them. It also provide the data on how children would response to the teaching method and materials that the teacher gave them.
