In the studies by flavell (1999), children were presented with a box on which there were pictures of candy. three and four-year-old children believed that the box contained candy. the children saw that the box contained crayons once it was opened. the three-year-old believed that other children would believe that the box contained crayons instead of candy. this demonstrates which principle?

This demonstrates "the false belief" principle

Explanation:

This is found in a study by Lavell (1999), which  has examined the role of age in the false belief understanding in typically developing children and to determine if the different type of false belief tasks affects performance on false belief. False belief understanding was measured in 72 children between the ages of 3 to 5 years old.  

the answer is true!