计算单支水平式牺牲阳极接地电阻的大小与（）因素有关。
A、阳极材料
B、填包料
C、阳极地床透气性
D、阳极电缆
参考答案：B
As we all know,________, the pollution will get worse and worse.
A．not if carefully dealt with
B．until not carefully dealt with
C．if not carefully dealt with
D．when not carefully dealt with
不完全变态的幼虫称若虫。
