The overall operating costs of many small farms are reduced when the

OFFICIAL EXPLANATION

B is the correct answer choice.

It would be impossible to argue reasonably that large farmers should use manure as fertilizer because they would realize even greater savings than the small farmers without also assuming that there is a sufficient amount of manure available for the fields of large farmers.

A is not the correct answer choice. The argument implies that it would be more cost effective for large farmers to eliminate commercial fertilizers and pesticides than it would be for small farmers to do so. The third answer is incorrect. No statements are made in the argument concerning treated sewage sludge and no assumption is made about it. D is not the correct answer choice. This statement is not assumed because if it were false—if large farmers seldom or never looked to small farmers for innovative ways of increasing crop yields or reducing operating costs—this would not affect anything relevant to the argument about the total savings that large farmers might gain by adopting new farming practices. E is also not the correct answer choice. It may well be true that the smaller the farm, the more control the farmer has over operating costs. However, with respect to control, the argument only that large farmers have enough control over their farming methods to adopt the recommended measures.