The correct response is:
The army wanted to use Iwo Jima to fuel up and bomb Japan.
Iwo Jima was strategically important because it was located roughly halfway between the Mariana Islands and Japan, making it a key location for staging air operations against the Japanese home islands. Capturing Iwo Jima allowed the Allies to establish airfields for long-range bombers to launch missions and provide fighter support for raids over Japan.