**Core Concept**
In this scenario, the patient is presenting with a condition known as placenta previa, where the placenta covers part of the internal cervical os. This can lead to vaginal bleeding, especially in the second or third trimester of pregnancy. The key concept here is the management of placenta previa to prevent maternal and fetal complications.

**Why the Correct Answer is Right**
The correct management of placenta previa involves bed rest to minimize the risk of vaginal bleeding. This is crucial as active bleeding can lead to maternal shock, fetal distress, and even maternal and fetal death. In this case, the patient is not actively bleeding, so bed rest is the appropriate management strategy. This allows for close monitoring and planning for potential delivery by cesarean section if bleeding occurs.

**Why Each Wrong Option is Incorrect**
**Option A:** Immediate delivery by cesarean section is not the best option as the patient is not actively bleeding, and immediate delivery could lead to unnecessary interventions and complications.
**Option B:** Hospitalization in a high-dependency unit is not necessary as the patient is stable and not actively bleeding.
**Option C:** Administering corticosteroids to enhance fetal lung maturity is not relevant as the primary concern is maternal and fetal stability, not fetal lung maturity.

**Clinical Pearl / High-Yield Fact**
It is essential to remember that placenta previa can be a life-threatening condition if not managed properly. Close monitoring and bed rest are crucial in preventing maternal and fetal complications.

**Correct Answer:** C. Bed rest to minimize the risk of vaginal bleeding.