What is the purpose of PAM in Linux?

The purpose of PAM, or Pluggable Authentication Modules, in Linux is to offer a flexible framework for authentication tasks. It allows system administrators to configure authentication methods for applications without needing to modify the underlying applications themselves. This modular approach means that different authentication technologies can be easily swapped in and out as needed, making it possible to implement various methods such as local password checks, LDAP, Kerberos, or biometrics seamlessly.

Using PAM, a centralized configuration file specifies how different authentication mechanisms are applied to various services. This capability streamlines the management of user authentication across the system, enhancing security and simplifying administration. Therefore, the option that states PAM provides pluggable authentication modules accurately captures its primary function within Linux systems.