When a process successfully calls exec$(),$ what happens to that process's file descriptor table?

File descriptor numbers $0$ through $3$ are left unchanged and descriptors $>3$ are automatically closed.

It is reset to the standard configuration where:

File Descriptor Number File Described

$0$ stdin $($keyboard$)$

$1$ stdout $($screen$)$

$2$ stderr $($screen$)$

It remains unchanged.

None of these