How did functional fixedness prevent the student from solving the problem and getting their pencil back?

While the student's physical reach could have been a factor in retrieving the pencil, the core issue in this context lies in functional fixedness rather than a limitation of physical ability. The emphasis here is on the cognitive aspect of problem-solving, not merely the physical execution of reaching.

The absence of extra pencils does not directly relate to the concept of functional fixedness, which specifically refers to a cognitive bias that limits a person's ability to see unconventional uses for familiar objects. While having spare pencils could have been a practical solution, it does not address the primary cognitive barrier of functional fixedness.

Moving the bookshelf represents a potential solution involving physical action rather than a cognitive obstacle like functional fixedness. While physical movement could have been a means to access the pencil, the core issue in this scenario pertains to the student's cognitive rigidity in perceiving the available tools.