Answer:
Option (C) is correct.
Step-by-step explanation:
In this situation, a firm will analyse the cost and benefits associated with the choice of installing the safety equipment or not.
Cost of installing the safety equipment is $5 per hour per employee
Hence, if the firm will pay $7 per hour less in the clean job than the wages paid to the employees in the dirty job then this will make the firm better off because the reduction in wages per hour per employee is greater than the cost of installing safety equipment per hour per employee.