Which component's update is described as a firmware update?

A firmware update specifically refers to modifying the software that is embedded directly into the hardware components of a device. Firmware acts as the bridge between the hardware and higher-level software, enabling essential functions and performance enhancements. This type of update typically involves making changes or improvements to the code that directly interacts with the hardware, which might include bug fixes, added features, or compatibility improvements with other hardware or software.

In contrast, visual interface enhancements are changes related to the user experience, often seen in the graphical user interface, but do not interact directly with the hardware. Hardware capacity expansion involves adding physical components, while network security updates focus on software that protects devices from security threats. These other options do not align with the definition or purpose of a firmware update, which is specifically tied to the software that operates within the device's hardware.