Which of the following, if true, provides the strongest support for Scott's argument? A. Companies have generally found that part-time employees are less productive than full-time ones. B. When the total number of hours worked at a company increases owing to the addition of more employees, the usual result is improved productivity at the company. C. When the total hours worked by all employees per week in two companies are equivalent, hourly productivity tends to be equivalent as well. D. Companies whose employees usually work a high number of hours tend to have greater total costs than do similar companies whose employees work fewer hours. E. Companies have found that total output per employee is not necessarily changed by reductions in the number of hours worked per employee.