A Thermometer Is Constructed by Filling a Small Glass Tube

A thermometer is constructed by filling a small glass tube with a liquid that expands linearly with temperature. The thermometer is then calibrated at 0°C and 100°C, and the scale evenly divided between the two values. Unfortunately, a manufacturing defect results in the middle one-third of the tube being narrower, otherwise the tube has uniform diameter. For what range of temperatures is the reading accurate?

A) 0°C to 33°C
B) 0°C and 67°C
C) 0°C to 33°C and 67°C to 100°C
D) 67°C to 100°C
E) At no point does this thermometer gives the right reading except at 0°C and 100°C.