Human beings could not benefit from experience in an emotionless world due to its lack of______.

A．It is a new design to keep people warm in winter.
B．It is closely sea!0d so that cool air cannot go through.
C．It is a new design without exhausting or harming natural resources.
D．It is created for gardening or fanning.

A．Because they are physically ill.
B．Because there is something wrong with their nerve.
C．The reasons are unknown.
D．Because they think it funny.