Concept:Tractor-hiring services aim to make farming easier and more affordable, not to raise farmer expenses.Explanation:Such services give farmers access to tractors without buying them, which promotes farm mechanization.They help farmers cultivate more land within a short time.They also increase farm output by speeding up operations, thereby boosting food production.But raising the cost of production is never an objective; tractor-hiring services are meant to lower or share costs, not increase them.Answer:C. increase the cost of production