哪种检查不用于诊断Friedreich型共济失调（）
A.心电图
B.超声心动图
C.X线片
D.CT和MRI
E.脑电图
参考答案：E
In 1965, a new Voting Rights Bill became law, ________all black people had the right to vote from then on.
A．by which
B．that
C．by what
D．which
简述景观中水的作用。
