— I am so glad that I caught you at home. I need your help!
— ____, John?
A:What else
B:So what
C:How come
D:What's up
21×6=____
20×6=____
32×4=____
27×3=____
刺鲍遇到危险时,身体会迅速鼓起,使硬刺竖起,形似刺球.这一现象说明( )