In Attempting to Solve the "Nine Dot Problem" Many Individuals

Multiple Choice

In attempting to solve the "nine dot problem" many individuals will not attempt to draw a line outside the imaginary boundary surrounding the nine dots. This is not a rule associated with the problem, but is imposed by the problem solver. What is this an example of?

A) trial-and-error learning
B) functional fixedness
C) mental set
D) unnecessary constraints