A previously healthy 58 years old man is admitted to the hospital because of an acute inferior myocardial infarction.Within several hours,he becomes oliguric and hypotensive(blood pressure is 90/60mmHg).Insertion of a pulmonary artery(Swan-Ganz)catheter reveals the following pressures:pulmonary capillary wedge-4mmHg;pulmonary artery-22/4mmHg:and mean right atrial-11mmHg.This man would best be treated with:

• A. Fluids
• B. Digoxin
• C. Dopamine
• D. Intraaortic balloon counterpulsation