Break even point of the firm is the point on a supply curve where _____

the firm earns only normal profits

The correct answer is option 1: the firm earns only normal profits

The minimum level of profit that is needed to keep a firm in the existing business is defined as normal profit. A firm that does not make normal profits is not going to continue in business. Normal profits are therefore a part of the firm’s total costs. It may be useful to think of them as an opportunity cost for entrepreneurship. Profit that a firm earns over and above the normal profit is called the super-normal profit. In the long run, a firm does not produce if it earns anything less than the normal profit. In the short run, however, it may produce even if the profit is less than this level. The point on the supply curve at which a firm earns only normal profit is called the break-even point of the firm. The point of minimum average cost at which the supply curve cuts the LRAC curve (in short run, SAC curve) is therefore the break-even point of a firm.