What is the primary role of the SD card in a portable device?

The primary role of the SD card in a portable device is to store non-volatile memory. Non-volatile memory is crucial because it retains data even when the device is powered off. This means that important information, such as photos, videos, music, and applications can be saved and accessed at any time without being lost when the device is shut down.

This storage capability allows users to expand their device's storage capacity easily, especially in devices like cameras, smartphones, and tablets, where internal memory might be limited. It provides flexibility for users to easily transfer files between devices or back them up.

In contrast, the other options focus on aspects that are not the primary function of an SD card. While increasing battery life, enhancing video resolution, or facilitating live streaming features may be important functionalities in portable devices, they do not accurately describe the main purpose of the SD card, which is primarily data storage.