‘Clove’ are

Clove is the dried, unopened flower bud of Syzygium aromaticum, a tree of the myrtle family (Myrtaceae). The buds are picked before they open and dried until they turn dark brown. So option D is correct.

• A) Nodules of stem: Stems do not form clove as a spice. Swellings sometimes seen on stems are galls or tubers, which have nothing to do with clove.
• B) Nodules of roots: Root nodules form in leguminous plants through symbiosis with Rhizobium, which fixes atmospheric nitrogen. Clove is not connected to this.
• C) Leaves: Clove leaves are distilled for clove oil, rich in eugenol. But the spice itself is the bud, so leaves are not the answer.

Core concept: economic botany, specifically spices and the plant part each one comes from. Cloves were central to the Spice Islands (Maluku) trade, and Indonesia and Zanzibar are major producers. For Mains, this links to GS-III on agriculture, value addition and spice exports under the Spices Board of India. Eugenol from clove oil is also used in dentistry.

Trap: Students mix up clove oil, which comes from the leaves, with the spice itself, which is the bud.