Question

when using stock images, a royalty - free license allows:
the purchaser to assume copyright of the image.
the image to be resold or transferred without paying a fee.
use of the image without paying a fee each time the image is used.
use of the image without purchasing a license.

Explanation:

A royalty-free license for stock images means the user pays a one-time fee for a license, then can use the image repeatedly without paying additional per-use royalties. It does not transfer copyright, allow reselling the license itself freely, or let users skip purchasing the license entirely.

Answer:

use of the image without paying a fee each time the image is used.