Briefing Zend Knowledge

which circumstances is the $_SESSION super-global available?

Under which circumstances is the $_SESSION super-global available? (Choose 2)

A.
If session_start() was called.

B.
If session.auto_start INI setting is enabled.

C.
Always available in PHP 5.

D.
If a valid session id is passed via GET, POST or COOKIE.

E.
If register_globals are enabled.