**Core Concept**
Cell motility is the process by which cells move in response to various stimuli. This movement is crucial for various physiological processes, including wound healing, immune response, and embryonic development. Cell motility is primarily facilitated by the cytoskeleton, which provides the mechanical framework for cell movement.

**Why the Correct Answer is Right**
The correct answer is **actin filaments**. Actin filaments, also known as microfilaments, are one of the three main components of the cytoskeleton. They are composed of actin proteins and play a crucial role in cell motility by forming dynamic structures that allow cells to move. Actin filaments interact with motor proteins such as myosin, which generates the force necessary for cell movement. In non-muscle cells, actin filaments are involved in the formation of stress fibers, which are dynamic structures that allow cells to change shape and move.

**Why Each Wrong Option is Incorrect**
* **Option A:** Microtubules are another component of the cytoskeleton, but they are primarily involved in maintaining cell shape and organizing intracellular transport. While microtubules can interact with motor proteins, they are not directly responsible for cell motility.
* **Option B:** Myosin is a motor protein that interacts with actin filaments to generate force for cell movement. However, it is not the primary component responsible for cell motility.
* **Option D:** The Golgi apparatus is a complex organelle involved in protein modification and secretion. It is not directly involved in cell motility.

**Clinical Pearl / High-Yield Fact**
In pathological conditions, alterations in actin filament dynamics can lead to abnormal cell motility, contributing to diseases such as cancer and cardiovascular disease.

**Correct Answer:** C.