Hearing aids make ________ possible for people with hearing problems to use the telephone and even to listen to music.

A．How could you consider the suggestion I put forward as useless
B． You’d better think carefully before you make comments on my idea.
C．You’d better stop expecting me to bring up a lazy and irresponsible child.
D．How could you doubt my ability to provide a proper education to my child

A．It is clear that too many people are involved in an invention.
B．Strictly speaking, an invention never comes from a single person.
C．The truth is that an invention needs almost everyone’s participation.
D．It is true that no man’s achievement can be regarded as an invention.