Final answer:
Oxytocin is primarily responsible for labor contractions. Terbutaline can be used to stop contractions.
Step-by-step explanation:
Oxytocin is primarily responsible for the contractions during labor. The posterior pituitary continuously produces oxytocin which causes muscular contractions in the uterus. As labor nears, oxytocin stimulates stronger and more painful contractions.
Terbutaline, on the other hand, is a medication that can be used to stop contractions. It belongs to a class of drugs called beta-adrenergic agonists and works by relaxing and opening the air passages to the lungs. However, it is not typically used to stop contractions during labor.
Therefore, the correct answer is C) Administer terbutaline as it can be used to stop contractions.