As Long as the Marginal Product of Labour Is Positive,a

As long as the marginal product of labour is positive,a

A) firm should continue to hire additional workers.
B) firm's profit will always rise as additional workers are hired.
C) firm's profit will always be positive as additional workers are hired.
D) firm's total output will always rise as additional workers are hired.
E) firm's total output will always rise,but its average output will always fall,as additional workers are hired.