Answer:
The correct answer is option b.
Step-by-step explanation:
A firm is able to maximize it's profit by producing output at the level where the marginal revenue earned from the last unit of output is equal to marginal cost incurred on it.
If a firm is operating at the point where the marginal revenue is lower than the marginal cost then the firm can maximize profit by reducing its output till the point where the marginal revenue and marginal cost are equal.