He won the scholarship. He ______ hard these terms.

A．they do not have branches
B．they do not have flowers
C．they do not have seeds
D．they do not need sunlight

A．the stronger it becomes
B．the more sunlight it will get
C．the thinner it will be
D．the thicker it will be

A．earning their living and keeping promises
B．doing practical jobs and facing reality
C．doing what they have promised
D．realizing what they were expected