**Core Concept**
Respiratory Distress Syndrome (RDS) is a condition that primarily affects premature infants, characterized by difficulty in breathing due to a lack of surfactant in the lungs. Surfactant is a substance that reduces the surface tension of the alveoli, allowing for easier lung expansion and preventing atelectasis.

**Why the Correct Answer is Right**
Surfactant deficiency in RDS leads to increased surface tension, which causes the alveoli to collapse, resulting in difficulty in breathing. Surfactant also helps to maintain the alveolar structure and prevents the alveolar-capillary membrane from collapsing. This is essential for gas exchange to occur.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as surfactant deficiency is a hallmark of RDS.
* **Option B:** This option is incorrect as surfactant replacement therapy is a common treatment for RDS.
* **Option D:** This option is incorrect as surfactant is essential for maintaining the alveolar structure and preventing atelectasis.

**Clinical Pearl / High-Yield Fact**
Surfactant deficiency in RDS can be caused by a genetic mutation in the surfactant protein-B (SP-B) gene, leading to a family history of RDS.

**Correct Answer: A. Surfactant deficiency is not a cause of RDS.**