What Is the Direct Manufacturing Labour Partial Productivity,assuming 40 000

What is the direct manufacturing labour partial productivity,assuming 40 000 units were produced during 2018 and 160 000 direct manufacturing labour-hours were used?

A) 0.25 unit per direct manufacturing labour-hour
B) 0.75 unit per direct manufacturing labour-hour
C) 0.50 unit per direct manufacturing labour-hour
D) 1.00 unit per direct manufacturing labour-hour