If you want a job of taking care of children, which ad will you answer().

单项选择题Which of the following words best describes mum().

A．Polite.
B．Patient.
C．Changeable.
D．Clever.

单项选择题Few ballet performers become nearsighted because ().

A．the reason remains to be seen
B．they have special food for themselves as dancers
C．they have special ways to keep slim
D．they dance on their tiptoes