Which of the following drug is the vasopressor of choice in pregnancy?

Ephedrine is a mixed alpha and beta adrenergic agonist and is the vasopressor of choice for treatment of hypotension in obstetric practice because of its protective effect on uterine blood flow in gravid uterus. It increases the cardiac output. Another vasopressor of choice in the treatment of hypotension in in pregnant woman is phenylephrine. It increases the peripheral aerial tone to a great extent. Recent evidence does not suppo ephedrine as superior to phenylephrine in treating hypotension in pregnancy. Recently its use was found to be associated with decreased fetal pH, worsening maternal blood pressure control, and increased nausea and vomiting. Ref: Obstetric Anesthesia: Principles and Practice edited by David H. Chestnut page 618.