The correct option is A wheat and rice
During the Green Revolution in the 1960s, Indian farmers cultivated wheat and rice using high yielding variety (HYV) seeds, irrigation, chemical fertilisers, insecticides, pesticides, and more. These HYV seeds could produce a lot more grains on a single plant than regular seeds. As a result, the same piece of land could produce far larger quantities of foodgrains than was possible earlier.