The correct option is C Both A and B
Microorganisms are both beneficial and harmful to us. Some microorganisms cause diseases called as pathogens. They can cause diseases in plants and animals both like in humans, common cold, tuberculosis, measles, chicken pox, polio, cholera, typhoid, hepatitis-B, malaria etc., and in plants, yellow mosaic fever, blast of wheat, brown spot etc. Some microorganisms like yeast, lactobacillus are used for the formation of food products such as curd, cheese, bakery products, idli, dosa etc. Thus, the correct answer is option C.