What can the tee command be used for?

A.
Print the contents of a file in reverse order

B.
Use the output of one command as arguments to another

C.
Add line numbers to the output of a command

D.
Pipe the output of one command into the input of another

E.
Send a command’s output to stdout and to a file at the same time

Explanation:
From the man pages:
tee – read from standard input and write to standard output and files