What is the purpose of the Solaris cryptographic framework metaslot?

A.
It is a storage facility for all of the encryption algorithms.

B.
It is a pointer to the next available cryptographic token slot.

C.
It is a library to limit algorithms based on export control laws.

D.
It is a door-based interface to the kernel cryptographic services.

E.
It is an interface to connect to any available cryptographic service.