Thermistor resistance decreases with increasing temperature (NTC type)

Steps:

• Initial total resistance: 12V / 0.10A = 120Ω, so initial R = 120Ω - 40Ω = 80Ω.
• New total resistance: 12V / 0.12A = 100Ω, so new R = 100Ω - 40Ω = 60Ω.
• Resistance drops from 80Ω to 60Ω, indicating temperature increase for NTC thermistor.
• New resistance is 60Ω at higher temperature.

Why A is correct:

• NTC thermistors follow the principle that resistance decreases as temperature rises, matching the observed current increase and R=60Ω.

Why the others are wrong:

• B: Temperature decreases would increase resistance for NTC, but resistance fell.
• C: 100Ω exceeds initial 80Ω, implying resistance rise inconsistent with current increase.
• D: Temperature increase with R=100Ω wrongly suggests resistance rise, opposite of NTC behavior.

Final answer: A