It has been found that major plant diseases and insect outbreaks are less likely to occur in a natural field than on a conventional farm because

• A. In conventional farming practices, use of pesticides, kill both useful and harmful insects indiscriminately. Therefore, insect outbreaks are often seen in conventional farms
• B. Fertilisers are used in conventional farming to increase yield. The increase in crop yield will consequently increase the diversity of pests
• C. In natural field, the biodiversity sustains a complex system which checks and balances insects at a manageable levels
• D. Both (a) and (c).