The correct option is A 1 - a, 2 - a, 3 - b, 4 - c
There is a significant amount of crop loss caused due to diseases caused by a wide range of fungal, bacterial and viral pathogens, especially in tropical climates. Some fungal diseases in crops are rusts, e.g., brown rust of wheat, red rot of sugarcane and late blight of potato. Crops are also affected by bacterial and viral infections. For example, black rot of crucifers and turnip mosaic disease respectively.