Answer: Incorrect; Correct; Incorrect
Step-by-step explanation:
A. This is incorrect. Increasing returns to scale refers to the situation whereby the long-run average cost curve of a firm slopes downward and this leads to an increase in the scale of production of the firm and this also leads to lower average costs.
B. This is correct. The constant returns to scale refers is a situation whereby an increase in the firm's scale of production will have no impact on the costs per unit produced.
C. This is incorrect. Decreasing returns to scale is a situation that occurs when the long-run average cost curve of a firm slopes upward and this results into a situation whereby an increase in the scale of production of the firm will lead to higher average costs.