The correct option is
C Euphorbia
Euphorbia is a petroleum plant. It produces hydrocarbons known as terpenoids which are similar to petroleum. It belongs to Euphorbiaceae family. The latex of this plant can be converted to useful fuels. About 20 tonnes of dry matter per hectare per year is produced by this plant. The latex is converted into natural gas and gasoline. Gasoline is used as an alternative fuel in vehicles.
So, the correct answer is 'Euphorbia'.