Sentence Correction

The more people that move to western states, which is an already overburdened ecosystem, the more
pressure on water resources becomes increasingly great, eventually requiring the diversion of major
rivers and the construction of dams.
"¢ The more people that move to western states, which is an already overburdened ecosystem, the more
pressure on water resources becomes increasingly great
"¢ The more that people move to western states, which is an already overburdened ecosystem, the
greater the pressure is on water resources
"¢ With more people moving to western states, an already overburdened ecosystem, the more pressure
on water resources becomes increasingly great
"¢ The more that people move to western states, an already overburdened ecosystem, the greater the
pressure on water resources becomes
"¢ The more people move to western states, which are already an overburdened ecosystem, the greater
the pressure on water resources becomes

OA E
The correct idiom is the more X, the more Y, but in the correct answer choice, the idiom -> the more X, the greater Y.. Is this usage ok?