Which of the following word includes a suffix (后缀)

A．Each of us supposed to go all out for the team on the sports field.
B．It is known to us that practice makes perfect.
C．It is necessary for us to master a foreign language skillfully.
D．We find it rather difficult to prevent people from doing that.

A．We should protect trees from being destroyed.
B．Women fail to get the equal rights in some countries.
C．She is the only one among the women writers who writes stories for children.
D．In old China we could not make a nail, let alone machines.