Which of the following is the smallest of these data storage capacities?

Two kilobytes is 2048 bytes, which is the smallest of the given capacities.

The value 2049 bytes is just one byte larger than two kilobytes.

The value 0.5 megabytes is about 512 kilobytes, far larger than two kilobytes.

The value 3 gigabytes is the largest by a wide margin, running into billions of bytes.

Converting every value to bytes lets them be compared on a single scale.

One kilobyte is 1024 bytes, one megabyte is 1024 kilobytes and one gigabyte is 1024 megabytes.