**Core Concept**
The question is testing the ability to identify a neuromuscular blocker that can cross the placenta, which is a critical consideration in obstetric anesthesia. This requires knowledge of the pharmacokinetic properties of various neuromuscular blockers, particularly their ability to cross the placental barrier.

**Why the Correct Answer is Right**
The correct answer is Vecuronium. Vecuronium is a non-depolarizing neuromuscular blocker that can cross the placenta due to its high lipid solubility and relatively low molecular weight. This property allows it to reach the fetus and potentially cause neuromuscular blockade, which can be a concern in obstetric anesthesia.

**Why Each Wrong Option is Incorrect**
* **Option A:** Pancuronium is a non-depolarizing neuromuscular blocker, but it is not known to cross the placenta due to its high molecular weight and low lipid solubility.
* **Option B:** Rocuronium is a non-depolarizing neuromuscular blocker that can be used in obstetric anesthesia, but it is not known to cross the placenta.
* **Option C:** Atracurium is a non-depolarizing neuromuscular blocker that undergoes Hofmann elimination, which makes it less likely to cross the placenta.

**Clinical Pearl / High-Yield Fact**
It is essential to choose a neuromuscular blocker that does not cross the placenta when administering anesthesia in labor or during cesarean section. Vecuronium is a good alternative, but its use should be judicious and carefully considered.

**Correct Answer:** C. Vecuronium.