A fuse is the most common type of protection against a short-circuit fault in LV distribution circuits, motor circuits and for portable appliances. What is a major drawback or deficiency with the use of fuse?

Correct Answer: Option A — It is insensitive to small over current.

Fuses are inherently less precise than circuit breakers regarding small overcurrents. Because they rely on the physical melting of a metal element, they are often insensitive to minor, long-term overloads that do not generate sufficient heat to melt the link, potentially leading to gradual insulation degradation over time.