The underlined word "impair" at the end of Paragraph 2 can be best replaced by ______.

A．people should be encouraged to donate their organs after death
B．organ removal is not legally permitted under any conditions in any country
C．organ removal should be advocated because it benefits the human society
D．organ removal is considered legal unless the dead person stated otherwise in his lifetime

A．shyness helps us to live up to our full potential.
B．Shyness enables us to understand ourselves better.
C．Shyness blocks our chances for a rich life.
D．Shyness has nothing to do with lack of self-esteem.