When I talked with my grandma on the phone, she sounded weak, but by the time we ________up, her voice had been full of life.

A．were hanging

B．had hung

C．hung

D．would hang

某同学将一小块金属钠放入烧杯内的水中反应，下列描述错误的是

A．钠与水反应放出的热使钠熔成一个小球

B．钠浮在水面上，四处游动

C．钠消失后，向烧杯中滴入几滴酚酞试液，溶液仍为无色

D．钠消失后，在烧杯中投入少量铝，有气体产生