Answer:
The correct option is (I) increase in marginal cost for the firms in the industry
Step-by-step explanation:
According to the given scenario, when there is a rise in increase in the workers wages in a purely competitive industry so the production cost would also rise that results in an increment in the marginal cost also the maximize profit arises when the marginal cost is equivalent to the marginal revenue
Therefore as per the given scenario, the correct option is (I)