下列说法正确的是[ ]
A．蛙是体内受精、变态发育
B．鸡是体内受精、体内发育
C．蛙是体外受精、变态发育
D．鸡是体外受精、体内发育
答案：C
一个正方体的棱长缩小2倍，它的体积就缩小[ ]
A．2倍
B．4倍
C．6倍
D．8倍
Never eat food that stays over night, it tastes .
A．if, good
B．but, well
C．even though, good
D．even if, well
