Mr Blacker Has Been Transferred to the Ward Following a Heart

Mr Blacker has been transferred to the ward following a heart attack three days ago. He tells you he is nauseated and feels quite unwell. You are assisting the registered nurse to care for him. The following four questions relate to his care.
-Intravenous frusemide 30 mg has been ordered. If available stock is 20 mg/ml, the registered nurse should give him

A) 3 ml
B) 2.5 ml
C) 2 ml
D) 1.5 ml