The Manager of an Amazon Fulfilment Center Estimates That Hiring

The manager of an Amazon Fulfilment Center estimates that hiring another shipping clerk would increase total revenue by $700 per week and increase total cost by $600 per week.He should _____

A) hire another clerk if the cost is less than $600.
B) hire another clerk regardless of the cost.
C) not hire another clerk if the revenue is greater than $700.
D) not hire another clerk regardless of the revenue.
E) hire another clerk because revenue would increase by $100 per week.