**Core Concept:** Acute femoral embolism refers to the sudden occlusion of blood flow in the femoral artery caused by the migration of emboli, typically from the heart or lower limbs, leading to severe limb ischemia.

**Why the Correct Answer is Right:** The correct answer, **D**, is the administration of systemic thrombolytic therapy, such as intravenous streptokinase. Thrombolytic therapy involves breaking down blood clots using enzymes, in this case, streptokinase, which degrades fibrin in the clot, restoring blood flow and preventing potential limb or life-threatening complications.

**Why Each Wrong Option is Incorrect:**

A. **Option A**: Intravenous thrombolysis (with alteplase) is a valid treatment option but is not the most appropriate for acute femoral embolism. Intravenous thrombolysis is typically reserved for pulmonary embolism and superficial femoral artery embolism.

B. **Option B**: Surgery, such as embolectomy, is a surgical procedure to remove the embolus and is not suitable for all cases, especially when the embolus is large or has already caused significant damage.

C. **Option C**: Antithrombotic medications like heparin or aspirin are anticoagulants, not thrombolitic agents. They primarily prevent clot formation and do not directly break down existing clots like thrombolytic therapy.

**Clinical Pearl:**

In acute femoral embolism, the management depends on the embolus size, location, and the severity of limb ischemia. In cases where surgical intervention is required due to large or distal emboli, a combination of thrombolytic therapy and surgery may be necessary. However, the primary focus is on administering systemic thrombolytic therapy to prevent complications and restore blood flow in most cases.

**Correct Answer Explanation:** Thrombolytic therapy, specifically intravenous streptokinase, is the preferred choice for acute femoral embolism due to its ability to break down fibrin in blood clots and restore blood flow. However, the specific treatment approach depends on the clinical context, patient status, and the severity of ischemia.