Soil that is rich in organic matter ______.
A. has had nothing added to it
B. provides vegetable matter with vitamins and minerals
C. contains unused vegetable matter
D. has had chemicals and fertilizers added to it
A．“1、2”对线与“3、6”对线位置交换B．“4、5”对线与“7、8”对线位置交换C．“1、2”对线与“4、5”对线位置
A. “1、2”对线与“3、6”对线位置交换
B. “4、5”对线与“7、8”对线位置交换
C. “1、2”对线与“4、5”对线位置交换
D. “3、6”对线与“7、8”对线位置交换
微信支付 
支付宝支付