Which one of the following is ‘sticky rice’ and is a common variety of rice in…

Concept: Rice varieties differ in their starch composition — grains with a very low amylose and high amylopectin content are termed “glutinous” or “sticky” rice, since they clump together on cooking; every major rice-growing region tends to have its own indigenous glutinous landrace, distinct from ordinary non-sticky table rice grown in the same region.

Application: Assam's indigenous glutinous rice landrace is Bora rice (also called “Bora saul”) — a native, low-amylose variety long cultivated across the state and used in traditional Assamese preparations such as pitha and other local sweets. It is this specific sticky-rice trait combined with Assam cultivation that the question is pointing to.

Cross-check — the remaining varieties belong to entirely different regions and do not share this Assam-glutinous profile:

• Arborio rice is an Italian medium-grain variety grown in the Po Valley, prized for the starch it releases into risotto — a different property from glutinous stickiness, and unconnected to Assam.

• Bomba rice is a Spanish variety grown around Valencia, valued for absorbing broth in paella while staying separate-grained — the opposite of a sticky/glutinous texture — and has no link to Assam.

• Ponni rice is a non-glutinous variety developed for and grown mainly in Tamil Nadu, used for idli, dosa, and plain steamed rice; it is neither sticky in the glutinous sense nor an Assamese variety.

Since only Bora rice matches both criteria — a glutinous/sticky grain and a variety native to Assam — it is the correct answer.