**Core Concept**
Placenta previa is a condition where the placenta partially or completely covers the internal cervical os, leading to potential severe bleeding during pregnancy or delivery. The severity of the condition necessitates a careful management approach to prevent maternal and fetal morbidity.

**Why the Correct Answer is Right**
In cases of severe placenta previa, the primary goal is to prevent further bleeding and ensure a safe delivery for both the mother and the fetus. The treatment involves bed rest, close monitoring of the mother's condition, and a scheduled cesarean delivery when the fetus is mature. This approach minimizes the risk of severe bleeding and allows for careful planning and preparation for the delivery.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because immediate delivery, especially vaginal delivery, is not recommended in cases of severe placenta previa due to the high risk of severe bleeding.

**Option B:** This option is incorrect because blood transfusion alone does not address the underlying issue of placenta previa and may not be sufficient to manage potential bleeding.

**Option C:** This option is incorrect because surgical evacuation of the placenta is not typically recommended in cases of severe placenta previa, especially before the fetus is mature.

**Clinical Pearl / High-Yield Fact**
In cases of severe placenta previa, the key management principle is to prioritize the mother's safety by preventing further bleeding and ensuring a safe delivery. A scheduled cesarean delivery is often the best approach when the fetus is mature.

**Correct Answer: C. Scheduled cesarean delivery when the fetus is mature.**