**Core Concept**
Autophagy is a vital cellular process where damaged organelles and protein aggregates are degraded and recycled, maintaining cellular homeostasis and promoting survival under stress conditions. This process involves the formation of double-membraned autophagosomes that eventually fuse with lysosomes, breaking down the contents.

**Why the Correct Answer is Right**
The correct answer involves the enzyme that plays a crucial role in autophagy. The enzyme, **Atg4**, is responsible for processing and activating other autophagy-related proteins, such as **LC3** (Microtubule-associated protein 1A/1B light chain 3), which is essential for autophagosome formation. The process of autophagy is tightly regulated by various signaling pathways, including the **mTOR** (mechanistic target of rapamycin) pathway, which acts as a sensor of cellular nutrient availability.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not specify a known enzyme involved in autophagy. While some proteins may be involved in autophagy-related processes, they are not the primary performers of autophagy.
* **Option B:** This option is incorrect because it is a lysosomal enzyme involved in protein degradation, but it is not directly responsible for the process of autophagy.
* **Option C:** This option is incorrect because it is a protein involved in protein synthesis and is not directly related to the process of autophagy.

**Clinical Pearl / High-Yield Fact**
Understanding the process of autophagy is crucial in the context of various diseases, including neurodegenerative disorders, cancer, and infectious diseases. The dysregulation of autophagy has been implicated in the pathogenesis of these conditions, making autophagy a potential therapeutic target.

**Correct Answer: C. Autophagy is primarily performed by the enzyme Atg4, which is involved in the processing and activation of other autophagy-related proteins.**