**Core Concept**
Primary pulmonary tuberculosis (TB) is the initial infection of the lungs by Mycobacterium tuberculosis. It typically occurs in previously uninfected individuals and is characterized by an immune response that attempts to contain the infection.

**Why the Correct Answer is Right**
The correct answer is related to the pathophysiology of primary pulmonary TB. In primary pulmonary TB, the bacteria usually lodge in the lung's apical or posterior segments. The immune response to the infection leads to the formation of a Ghon complex, which includes a focus of caseating granulomatous inflammation in the lung parenchyma. The Ghon complex is often accompanied by lymphadenopathy, particularly in the hilar or paratracheal regions.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as primary pulmonary TB typically does not present with cavitation, which is more characteristic of secondary or post-primary pulmonary TB.
**Option B:** This option is incorrect as primary pulmonary TB is not typically associated with the formation of a fistula between the lung and the pleural space.
**Option C:** This option is incorrect as primary pulmonary TB is not typically associated with the presence of a large pleural effusion.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that primary pulmonary TB often presents with an indolent course and may be asymptomatic, highlighting the importance of screening and testing for latent TB infection in high-risk populations.

**Correct Answer:** C.