Although cats cannot see in complete darkness their eyes are much more __________ to light than are human eyes.

　　A) glowing

　　B) brilliant

　　C) sensitive

　　D) gloomy

　　注：1. sensitive 敏感的

　　2. glowing 兴高采烈的

　　3. brilliant 聪明的

　　4. gloomy 郁闷的

　　While nuclear weapons present grave ________ dangers, the predominant crisis of overpopulation is with us today.

　　A) inevitable

　　B) constant

　　C) overwhelming

　　D) potential

　　注：1. potential 潜在的

　　2. constant 常数

　　3. inevitable 不可避免的

　　4. overwhelming 占绝大多数的，压倒一切的

　　This is the ______ piano on which the composer created some of his greatest works.

　　A) true

　　B) original

　　C) real

　　D) genuine