**Core Concept**
Cell lysis by the complement system is a process where the complement proteins interact with the cell membrane of a target cell, leading to its destruction. This process involves the formation of a membrane attack complex (MAC) that creates pores in the cell membrane, causing the cell to lyse.

**Why the Correct Answer is Right**
The correct answer is related to the formation of the membrane attack complex (MAC). The MAC is formed through the sequential assembly of C5b, C6, C7, C8, and multiple C9 molecules. This assembly creates a pore in the cell membrane, allowing ions and water to flood in and causing the cell to lyse. The MAC is the final step in the complement cascade, leading to the destruction of the target cell.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not describe the correct mechanism of cell lysis by the complement system.
* **Option B:** This option is incorrect because it is not related to the formation of the membrane attack complex (MAC).
* **Option C:** This option is incorrect because it does not accurately describe the role of the complement system in cell lysis.

**Clinical Pearl / High-Yield Fact**
The complement system is an important part of the innate immune response, and its dysregulation can lead to various diseases, including autoimmune disorders and infections. Understanding the mechanism of cell lysis by the complement system is crucial for developing effective treatments for these conditions.

**Correct Answer: C. Membrane attack complex (MAC)**