Which method will reduce the number of file handles in use?

While reviewing the MySQL error log, you see occasions where MySQL has exceeded the
number of file handles allowed to it by the operating system. Which method will reduce the
number of file handles in use?

A.
Activating the MySQL Enterprise thread pool plugin

B.
Relocating your data and log files to separate storage devices

C.
Disconnecting idle localhost client sessions

D.
Implementing storage engine data compression options