The European Central Bank yesterday      the document was genuine but refused to make any further comment.

A．expected

B．suggested

C．confirmed

D．concluded

爆炸帽是压力容器安全附件的一种，爆破帽为中间具有一薄弱断面的厚壁短管，破压力误差较小，泄放面积较小，多用于( )容器。

A．低压
B．高压
C．中压
D．超高压