The healthcare provider prescribes oxytocin synthetic 10 units/L via IV drip to augment a client's labor because she is experiencing a prolonged active phase. Because the client is receiving oxytocin, the nurse should closely monitor for which complication?

A. Fetal tachycardia can occur as a sign of fetal distress but is not the primary complication directly linked to oxytocin administration. B. Hemorrhage is more often a postpartum complication rather than an immediate risk during oxytocin infusion for labor augmentation. C. Uterine tetany (tachysystole) is a major risk of oxytocin use because excessive stimulation can lead to sustained contractions, reducing placental blood flow and causing fetal distress. Close monitoring of contraction frequency and duration is essential. D. Uterine hypostimulation is the opposite effect of oxytocin and is not the concern when the medication is being administered to increase contractions.