**Core Concept**
The management of a sudden choking episode due to a foreign body involves rapid and effective measures to secure the airway and remove the obstruction. This situation often requires immediate action to prevent asphyxiation.

**Why the Correct Answer is Right**
The correct approach is to perform the Heimlich maneuver, also known as abdominal thrusts. This technique helps to dislodge the foreign body from the airway by creating a sudden increase in pressure within the thoracic cavity. The Heimlich maneuver involves a series of quick compressions to the abdomen, just below the ribcage, to force the air out of the lungs and potentially dislodge the foreign body.

**Why Each Wrong Option is Incorrect**
**Option A:** Back blows are sometimes used in conjunction with the Heimlich maneuver but are not the primary method for managing sudden choking due to a foreign body. They may be used in specific situations, but the Heimlich maneuver is generally considered the first line of management.

**Option B:** This option is not relevant to the management of sudden choking due to a foreign body. The use of a nasogastric tube or gastric lavage is not indicated in this situation.

**Option C:** This option is incorrect as it is not a recommended first-line management for sudden choking due to a foreign body. The use of oxygen therapy may be beneficial in other situations but is not directly applicable to this scenario.

**Clinical Pearl / High-Yield Fact**
In the event of a choking emergency, the Heimlich maneuver should be performed with the person standing upright, if possible, to facilitate the effectiveness of the abdominal thrusts.

**Correct Answer:** C. Heimlich maneuver.