Answer:
C. The firms in this industry have diseconomies of scale.
Step-by-step explanation:
Diseconomies of scale arise when the business expands so its cost per unit rises at the time when the output is also increased so ultimately the cost is also increased
in this, the firm experience excessive average cost that result in lower productivity as compared before when there is an increase in output
Therefore according to the given situation, the third option is correct as it fits the given scenario