Final answer:
In MySQL, option files are also known as .mycnf, which are used to store server and client configurations to avoid repetitive command-line entries.
Step-by-step explanation:
The option files in MySQL, also known as configuration files, are used to specify options for MySQL programs so that the same options do not have to be provided every time a program is run. The correct answer to what another name for the option files is: d) .mycnf. This file contains settings for the MySQL server and client applications and can be found in various locations on the system, with different versions being applicable in different contexts, such as system-wide or user-specific configurations.