Which one of the following is a bio-diesel crop?

Cotton
Sugarcane
Jatropha
Potato

The correct answer is (c), Jatropha. Jatropha is a shrub or small tree that is native to tropical and subtropical regions of the Americas, Africa, and Asia. It is a fast-growing plant that can be grown on marginal land, and its seeds contain a high oil content that can be used to produce biodiesel. Biodiesel is a renewable fuel that can be used in diesel engines, and it is a cleaner-burning alternative to petroleum diesel.

Cotton (a) is a fiber crop that is grown for its long, strong fibers. Sugarcane (b) is a grass that is grown for its sweet juice, which is used to make sugar, ethanol, and other products. Potato (d) is a starchy tuber that is a staple food in many parts of the world.

Jatropha is a better choice for biodiesel production than cotton, sugarcane, or potato because it is a fast-growing plant that can be grown on marginal land, and its seeds contain a high oil content.