If you have a wireless card belonging to this class, say Y.

Note that the answer to this question doesn't directly affect the
kernel: saying N will just cause the configurator to skip all the
questions about these cards. If you say Y, you will be asked for
your specific card in the following questions.

For more information and documentation on this module you can visit:

https://wireless.wiki.kernel.org/en/users/Drivers/ath

For information on all Atheros wireless drivers visit:

https://wireless.wiki.kernel.org/en/users/Drivers/Atheros