Cookies and Cream Enterprise is currently a profit-maximising firm. They have decided to change their objective to sales maximisation, it can be deduced that Cookies and Cream Enterprise will move from setting prices at which: A. marginal revenue equals zero to where marginal revenue equals marginal costs B. marginal revenue equals marginal costs to where marginal revenue equals zero C. marginal revenue equals marginal costs to where average revenue equals average costs D. average revenue equals average costs to where marginal revenue equals marginal costs