The only liquid which is a good conductor of heat is A. water.B. turpentine.C. alcohol.D. mercury.

The only liquid which is a good conductor of heat is D. mercury.
Explanation:
• Mercury (Hg) is a liquid metal that is known to be an excellent conductor of heat. This is due to the free-moving metallic electrons that can transfer thermal energy efficiently. Mercury has high thermal conductivity, making it useful in applications such as thermometers and other temperature-sensitive instruments.
Other Liquids:
• Water (A), while it does conduct heat, is not as good as mercury. Water has moderate thermal conductivity and is often used as a coolant, but it is not considered a very efficient conductor compared to metals.
• Turpentine (B) and Alcohol (C) both have relatively low thermal conductivities. They are not efficient conductors of heat and are generally used in different contexts, such as solvents or fuels.
Thus, mercury stands out as the best conductor of heat among the options.
Correct Answer:
D. Mercury