**Core Concept**
The production of surfactant, a crucial substance that reduces surface tension in alveoli, is a vital aspect of lung physiology. Surfactant production is a complex process involving various cells and enzymes. This question tests the student's understanding of the cellular origin of surfactant.

**Why the Correct Answer is Right**
Surfactant is primarily produced by type II pneumocytes, also known as septal cells, in the alveoli of the lungs. These cells synthesize and secrete surfactant, a mixture of phospholipids and proteins, into the alveolar space. The surfactant reduces the surface tension in the alveoli, preventing alveolar collapse during exhalation and facilitating gas exchange. The production of surfactant is crucial for maintaining lung function and preventing respiratory distress syndrome in premature infants.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because while Clara cells in the bronchioles produce surfactant-like proteins, they are not the primary source of surfactant in the lungs.
**Option B:** This option is incorrect because alveolar macrophages are involved in the clearance of surfactant from the alveolar space, not its production.
**Option C:** This option is incorrect because while the lungs are responsible for gas exchange, they are not responsible for the production of surfactant.

**Clinical Pearl / High-Yield Fact**
A key clinical correlation to remember is that premature infants with respiratory distress syndrome often require surfactant replacement therapy to prevent alveolar collapse and improve lung function.

**Correct Answer:** C. Type II pneumocytes.