A poultry farmer was advised to dispose all his sick old stock and sanitize the poultry house before the arrival of his new purchased stock, what might be the reason for the advice? To _______

• A.avoid pecking and cannibalism in the farm
• B.meet up with the seasonal market demand
• C.raise more capital for the new purchase
• D.reduce the cost of old stock production
• E.reduce the spread of diseases in the farm