Users report that connections to a MariaDB service are being closed unexpectedly. A systems administrator troubleshoots the issue and finds the following message in /var/log/messages:

Which of the following is causing the connection issue?

A. The process mysqld is using too many semaphores.
B. The server is running out of file descriptors.
C. Something is starving the server resources.
D. The amount of RAM allocated to the server is too high.