**Core Concept**
Spontaneous pneumothorax occurs when there is a rupture of the alveoli leading to air leak into the pleural space, resulting in a decrease in lung volume and potentially life-threatening complications. The primary goal of treatment is to re-expand the lung and prevent further air leaks.

**Why the Correct Answer is Right**
The earliest treatment of choice for spontaneous pneumothorax is needle aspiration or small-bore chest tube insertion. This is because needle aspiration is a minimally invasive procedure that can rapidly re-expand the lung and relieve symptoms, whereas more invasive surgical interventions are typically reserved for cases that do not respond to initial management. The mechanism behind needle aspiration involves the temporary removal of air from the pleural space, allowing the lung to re-expand and reducing the risk of further complications.

**Why Each Wrong Option is Incorrect**
**Option A:** Chest X-ray is a diagnostic tool, not a treatment. While it can help confirm the diagnosis of spontaneous pneumothorax, it is not a suitable treatment option.
**Option B:** High-flow oxygen therapy may be used as an adjunct to treatment but is not a standalone treatment for spontaneous pneumothorax.
**Option C:** Surgical interventions, such as thoracotomy or video-assisted thoracic surgery (VATS), are typically reserved for cases that do not respond to initial management and are not the earliest treatment of choice.

**Clinical Pearl / High-Yield Fact**
Spontaneous pneumothorax often occurs in individuals with pre-existing lung conditions, such as chronic obstructive pulmonary disease (COPD) or cystic fibrosis, and in tall, thin males under the age of 40.

**Correct Answer:** C.