Which one of the following sometimes hinders the problem solving?

The correct answer is B) Mental set. A mental set is the tendency to keep using a strategy that worked earlier, even when a simpler or better route is available. Luchins' water-jar experiments (1942) showed this clearly: subjects who learned a long three-jar method kept using it even when a direct two-jar solution existed, and the earlier habit blocked the shorter answer.

Why the others are weaker choices:

• Heuristics are rule-of-thumb shortcuts. They usually speed up solutions. They mislead only in specific cases through biases, and textbooks treat them as aids rather than the standard obstacle.
• Analogy helps by mapping a known problem onto a new one, which is the basis of transfer learning. It hinders only when the analogy is wrong, which is not its defining character.
• Algorithms are step-by-step procedures guaranteed to reach a solution if correctly applied. They can be slow, but they do not block solving.

Concept link: this sits in the cognition and problem-solving part of General Mental Ability and connects to Mains discussions on rigid, routine-bound administrative thinking.

Trap: aspirants pick Heuristics because it is a familiar bias-related term, but the question asks for the factor that fixes the solver's approach to past methods, which is mental set.