Hint: To measure the boiling temperature of water $ \left( {{100}^{0}}C \right) $ , a thermometer must be capable of measuring temperatures up to this, that is, the upper point in its range should be more than $ {{100}^{0}}C $ . Clinical thermometers are usually used to measure human body temperatures which are lower.
Complete step-by-step answer:
The boiling point of water is $ {{100}^{0}}C $ . To measure the boiling point of water, a thermometer must be able to at least measure up to this temperature value.
Laboratory thermometers are specifically designed with the purpose of measuring high temperature values and boiling points of liquids. They can measure boiling points with high precision. They are made with high strength glass and given proper heat withstanding ability through processes like heat tempering and annealing. Hence, they can be easily used to measure the boiling point of water.
Hence, the correct option is B) Laboratory thermometers.
Note: Clinical thermometers are usually used to measure the temperature of the human body. They are not given so much strength and heat withstanding capacity as the laboratory thermometers since they do not require it for their primary purpose. Their range usually lies between $ {{35}^{0}}C $ and $ {{42}^{0}}C $ which is the range in which the temperature of the body can fluctuate.Hence, by no means, can they measure high temperatures like $ {{100}^{0}}C $ . So they cannot be used to measure the boiling point of water.