Correct option is C
Powdery mildew can be controlled using Bordo mixture and Suplhur. Bordeaux mixture (also called Bordo Mix) is a mixture of copper (II) sulphate (CuSO4) and quicklime (CaO)used as a fungicide. It is used in vineyards, fruit-farms and gardens to prevent infestations of downy mildew, powdery mildew and other fungi. Sulfur is an element that exists in nature and can be found in soil, plants, foods, and water. Sulfur can kill insects, mites, fungi, and rodents.