A,20=4乘以5.B,20=2乘以2乘以5.C,20=1乘以2乘以2乘以5.应该选哪一项,为什么?

问题描述:

A,20=4乘以5.B,20=2乘以2乘以5.C,20=1乘以2乘以2乘以5.应该选哪一项,为什么?

B,20=2乘以2乘以5