The correct option is B 1-b, 2-c, 3-d, 4-a
∙ Penicillin is the first discovered antibiotic, obtained from a fungus called Penicillium.
∙ Clostridium is a harmful bacteria which multiplies in warm food under anaerobic conditions and results in spoiling the food.
∙ Rhizobium found in root nodules of leguminous crops, fixes atmospheric nitrogen to nitrogenous compounds and supplies them to plants, providing nutrition.
∙ Yeast is a fungal microbe which feeds on carbon compounds releasing alcohol and carbon dioxide gas. This gas makes the bread spongy. Hence, yeast is used in bakery products.