Please answer a question about the following article about Pacific War:

The battle of Iwo Jima ("Operation Detachment") in February 1945 was one of the bloodiest battles fought by the Americans in the Pacific War. Iwo Jima was an 8 sq mile (21 km2) island situated halfway between Tokyo and the Mariana Islands. Holland Smith, the commander of the invasion force, aimed to capture the island, and utilize its three airfields as bases to carry out air attacks against the Home Islands. Lt. General Tadamichi Kuribayashi, the commander of the island's defense, knew that he could not win the battle, but he hoped to make the Americans suffer far more than they could endure.

How many airfields were on Iwo Jima?
three