the following are cereal crops except

Cereal crops are members of the grass family (Poaceae/Gramineae) cultivated primarily for their starchy, edible grains. Common examples include rice, maize (corn), millet, wheat, sorghum, barley, and oats.

Cowpea (Vigna unguiculata) is not a cereal. It belongs to the legume family (Fabaceae/Leguminosae). Legumes are dicotyledonous plants that produce seeds in pods and are cultivated mainly for their high protein content. Cowpea is also notable for its ability to fix atmospheric nitrogen through symbiotic bacteria (Rhizobium) in its root nodules.

Rice (Oryza sativa), maize (Zea mays), and millet (Pennisetum glaucum and related species) are all true cereals - monocotyledonous grasses that produce grain as their primary harvest product.

Exam tip: To distinguish cereals from legumes, remember that cereals are grasses (monocots) grown for carbohydrate-rich grains, while legumes are pod-bearing plants (dicots) grown for protein-rich seeds. Cowpea, groundnut, soybean, and beans are legumes, not cereals.