What is a small, portable secondary storage device that is about the size of a package of gum?

The correct answer is a flash drive because it is specifically designed to be compact, portable, and convenient for transferring and storing data. Flash drives utilize flash memory technology, which allows them to be small, reliable, and relatively lightweight—about the size of a package of gum, making them easy to carry around in a pocket or on a keychain.

External hard drives, although portable, are generally larger than a package of gum and are usually bulkier, designed for much more significant data storage capacity. CD-ROMs are discs that require a specific drive to read and are not portable in the same way as flash drives; they also tend to be more fragile and not as practical for convenient mobility. Memory cards, while small and capable of storing data, are typically used in specific devices like cameras and smartphones, making them less universally portable for file transfer purposes. Therefore, the characteristics of a flash drive align perfectly with the question's description.