**Core Concept**
Pleural effusion is the accumulation of excess fluid in the pleural space surrounding the lungs, which can be caused by various factors including infections, malignancies, and heart failure. The pleural fluid composition and characteristics can provide valuable diagnostic information.

**Why the Correct Answer is Right**
The correct answer is related to the characteristics of pleural effusion. Pleural effusion is typically classified as transudative or exudative based on the protein content of the fluid. Transudative effusions are caused by increased hydrostatic pressure (e.g., heart failure) or decreased oncotic pressure (e.g., cirrhosis), whereas exudative effusions are caused by inflammation, infection, or malignancy. In exudative effusions, the protein content is higher than 3g/dL, and the lactate dehydrogenase (LDH) level is also elevated.

**Why Each Wrong Option is Incorrect**
**Option A:** This statement is true about pleural effusion, as it is often associated with malignancy, tuberculosis, and other infections.
**Option B:** This statement is also true, as pleural effusion can be caused by heart failure, leading to increased hydrostatic pressure and transudative effusion.
**Option C:** This statement is incorrect because pleural effusion can be caused by a variety of factors, including infections, malignancies, and heart failure, but it is not exclusively associated with chronic kidney disease.

**Clinical Pearl / High-Yield Fact**
In patients with pleural effusion, the Light's criteria can be used to differentiate between transudative and exudative effusions: a pleural fluid protein-to-serum protein ratio of >0.5, a pleural fluid LDH-to-serum LDH ratio of >0.6, or a pleural fluid LDH level of >2/3 the upper limit of normal.

**Correct Answer: C.**