**Core Concept**
The free radical scavenging system, also known as antioxidant defense system, is a network of enzymes and molecules that protect cells from oxidative damage caused by free radicals. This system helps to maintain cellular homeostasis and prevent oxidative stress, which can lead to cell damage and disease.

**Why the Correct Answer is Right**
The enzyme responsible for free radical scavenging is Superoxide Dismutase (SOD). SOD catalyzes the conversion of superoxide radicals (O2-) to hydrogen peroxide (H2O2) and oxygen (O2). This reaction helps to neutralize the toxic effects of superoxide radicals and prevent oxidative damage to cellular components. SOD is a key enzyme in the free radical scavenging system and is found in various forms, including Cu-Zn SOD, Mn SOD, and Fe SOD.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is a distractor, as it is not directly related to the free radical scavenging system.
* **Option B:** This option is incorrect because it is a type of enzyme involved in carbohydrate metabolism, not free radical scavenging.
* **Option C:** This option is incorrect because it is a type of enzyme involved in lipid metabolism, not free radical scavenging.

**Clinical Pearl / High-Yield Fact**
SOD is an essential enzyme in protecting against oxidative stress, which is implicated in various diseases, including neurodegenerative disorders, cancer, and cardiovascular disease. Deficiencies in SOD have been linked to increased oxidative damage and disease susceptibility.

**Correct Answer: C. Catalase**