The option that is commonly used as an anaesthetic is CHCI3, which is also known as chloroform. Chloroform is a colorless liquid with a sweet smell, and it was widely used as an anaesthetic in the past. It works by depressing the central nervous system and inducing a state of unconsciousness. However, chloroform has been largely replaced by other anaesthetics due to its potential to cause liver damage and other health problems. Other options, such as C2H5OH or ethanol, may be used for sedation or pain relief but are not typically used as general anaesthetics.