**Core Concept**
In cases of foreign body aspiration, particularly in young children, the airway can become obstructed, leading to respiratory distress. The child's symptoms, such as intercostal retraction and increasing cyanosis, indicate a severe airway obstruction. A timely and appropriate intervention is crucial to prevent further complications.

**Why the Correct Answer is Right**
The Heimlich maneuver is a lifesaving technique that can be used in cases of foreign body aspiration. It involves a series of abdominal thrusts that help dislodge the object from the airway. The mechanism behind this technique is the increase in intra-abdominal pressure, which helps to push the object upwards and out of the airway. This is particularly effective in young children, as their airways are smaller and more susceptible to obstruction.

**Why Each Wrong Option is Incorrect**
**Option A:** CPR (Cardiopulmonary Resuscitation) - While CPR is essential in cases of cardiac arrest, it is not the primary intervention for foreign body aspiration.
**Option B:** Oxygen therapy - Although oxygen therapy may help alleviate the child's cyanosis, it does not address the underlying airway obstruction.
**Option C:** Bronchoscopy - While bronchoscopy can be used to remove foreign bodies, it is not the immediate intervention needed in this situation, and the child's airway may be compromised before a bronchoscope can be obtained.

**Clinical Pearl / High-Yield Fact**
In cases of foreign body aspiration, the Heimlich maneuver should be performed with the child in a prone position (on their stomach) to help dislodge the object.

**Correct Answer: C. Heimlich maneuver**