Degree of hotness or coldness of a body is measured by
Thermometer
The explanation for correct option(s):
Option C: Thermometer
The explanation for incorrect options:
Option A: Balance
It is a device used to measure weight.
Option B: Measuring Cylinder
It is a device used to measure the volume of liquids.
Option D: Barometer
It is a device used to measure the amount of air pressure in a certain environment.
Hence, the correct option is Option C. Thermometer.