According to the passage, cloning technology is ______.

A．people feel cloned children may not live longer than those naturally born
B．cloning technology is not so advanced that people feel doubts about it
C．it is so expensive that ordinary people have no access to it
D．it is not only costly and inefficient, but unacceptable as well

A．Because of the criticism, it has been stopped
B．Because of the opposition, it will be illegal for five years
C．Although it is criticized, it has made great progress
D．Although it is criticized, it is a perfect technology