Question 541General Subjects - Assistant Engineer

The correct answer is D) Thermistor. Thermistors are made of heat-treated metallic oxides and generally have a negative coefficient of resistance, meaning their resistance decreases as temperature increases. This property makes them well-suited for temperature sensing applications. The other options are incorrect because: A) Bimetallic devices use the differential expansion of two metals to measure temperature, B) Resistance temperature detectors (RTDs) use the positive temperature coefficient of resistance in metals like platinum, and C) Thermocouples generate a voltage in response to temperature changes, rather than relying on resistance.