What type of sugar forms the backbone of RNA?

Ribose sugar

The correct answer is Option (3) -Ribose sugar

RNA was the first genetic material. There is now enough evidence to suggest that essential life processes (such as metabolism, translation, splicing, etc.), evolved around RNA. RNA used to act as a genetic material as well as a catalyst (there are some important biochemical reactions in living systems that are catalysed by RNA catalysts and not by protein enzymes). But, RNA being a catalyst was reactive and hence unstable. RNA can serve as the genetic material in certain viruses, such as retroviruses like HIV.  RNA has ribose sugar as its backbone, not hexose sugar. Hexose sugars have six carbon atoms, while ribose has five. Certain RNA molecules, known as ribozymes, can act as catalysts and facilitate chemical reactions.