**Core Concept**
The scenario describes a case of molar pregnancy, specifically a missed hydatidiform mole with a coexisting non-viable intrauterine gestation. This is a rare but serious condition requiring prompt medical attention to prevent complications.

**Why the Correct Answer is Right**
The snowstorm appearance on ultrasound is characteristic of a molar pregnancy. The presence of a fetus with an absent heartbeat indicates a non-viable gestation. Suction evacuation is the recommended management option for a missed molar pregnancy with a coexisting non-viable fetus. This procedure involves the removal of the uterine contents using a suction device, which helps to prevent the risk of hemorrhage, infection, and the development of gestational trophoblastic neoplasia (GTN). The cervical os is closed, making suction evacuation a feasible option.

**Why Each Wrong Option is Incorrect**

**Option A:** Medical termination with vaginal misoprostol is not suitable for a missed molar pregnancy, as it may not effectively remove the uterine contents and can lead to incomplete evacuation.

**Option B:** Medical termination with an oxytocin infusion is not recommended for a missed molar pregnancy, as it may not address the underlying issue of a non-viable gestation and can lead to excessive uterine bleeding.

**Option D:** Performing a total abdominal hysterectomy is an overly aggressive approach and is not necessary for the management of a missed molar pregnancy with a coexisting non-viable fetus.

**Clinical Pearl / High-Yield Fact**
A missed molar pregnancy can be distinguished from a normal pregnancy by the presence of a "snowstorm" appearance on ultrasound, characterized by multiple small echogenic dots within the uterine cavity.

**✓ Correct Answer:** C. Perform suction evacuation