**Core Concept**
The patient likely has a tension pneumothorax, a life-threatening condition that requires immediate decompression to restore breathing and circulation. Tension pneumothorax occurs when air enters the pleural space and cannot escape, leading to increased intrathoracic pressure, mediastinal shift, and compromised cardiac output.

**Why the Correct Answer is Right**
Tension pneumothorax is characterized by the presence of a deviated trachea, hyperresonant sound on the affected side, and distended neck veins. The correct management involves inserting a large-bore needle (or cannula) into the second intercostal space in the mid-clavicular line on the affected side to decompress the pneumothorax. This is followed by the insertion of a chest tube to allow for the evacuation of air and re-expansion of the lung.

**Why Each Wrong Option is Incorrect**
**Option A:** Insertion of a nasogastric tube is not appropriate for tension pneumothorax management, as it does not address the underlying issue of air accumulation in the pleural space.
**Option B:** Administration of oxygen is essential, but it does not address the immediate need for decompression in a tension pneumothorax.
**Option C:** Insertion of a central line may be necessary for other reasons, but it is not the initial step in managing tension pneumothorax.

**Clinical Pearl / High-Yield Fact**
The "3 Ps" of tension pneumothorax are: **P**ain, **P**osterior displacement of the trachea, and **P**ulsus paradoxus (a drop in systolic blood pressure on inspiration). Remembering these signs can help you quickly diagnose and manage tension pneumothorax in a critically ill patient.

**Correct Answer:** C. Insertion of a large-bore needle into the second intercostal space in the mid-clavicular line on the affected side to decompress the pneumothorax.