Concept:The supply curve shows the direct relationship between price and quantity supplied.Explanation:The market supply curve slopes upward from left to right because price and quantity supplied move in the same direction.When the price of a commodity is lower, producers are willing to supply less of it.When the price is higher, producers are willing to supply more of it.So the upward slope means that at a lower price, less quantity is supplied.Answer:C. at a lower price, less is supplied.