The major component of LPG is:
 

LPG is liquified petroleum gas and is one of the constituents of petroleum and is extracted by fractional distillation of petroleum. LPG is a highly flammable gas and is used for cooking purposes at home. LPG is an odorless gas in its unprocessed state. It is really added to propane as a safety measure to give it the unique scent that consumers associate with LPG. Gas leaks might build up undetected in propane if there was no scent added. The stench of an altogether other substance called ethyl mercaptan is what we actually detect when there is a leak. When the gas leaves the primary storage terminals, this material is incorporated into the gas.

LPG is a mixture of hydrocarbons with major proportions of propane and butane.

Thus, the correct option is C.