but for water,it ---impossible to live in the desert

问题描述:

but for water,it ---impossible to live in the desert
a is
b was
c were
d would be
为什么,是表虚拟的假设,还是真实的呢

A
但是对于水而言,生存在沙漠中是不可能的.
用is 表示一般情况下的,或者表示真理