We all __________how he made such great progress in a short time.

A．believed

B．thought

C．decided

D．wondered

如果一侧颈内动脉阻塞或高度狭窄，同侧颈总动脉将出现哪种变化

A．阻力指数降低

B．阻力指数升高

C．收缩期峰值流速升高

D．舒张期峰值流速升高

E．血流反向