The correct answer is (a) Methanol.
Methanol is a colorless, flammable liquid that is used as a solvent, fuel, and antifreeze. It is also known as wood spirit because it can be produced by distilling wood.
Ethanol is a colorless, flammable liquid that is used as a solvent, fuel, and antiseptic. It is also known as grain alcohol because it can be produced by fermenting grain.
Formaldehyde is a colorless, flammable gas that is used as a preservative, disinfectant, and embalming fluid. It is also known as formalin.
Acetaldehyde is a colorless, flammable liquid that is used as a solvent, fuel, and intermediate in the production of other chemicals. It is also known as acetic aldehyde.
Methanol is the only option that is known as wood spirit.