Which was the last island that the allies captured before preparing to attack mainland japan?

The last island that the Allies captured was the island of Okinawa. This island is the largest of the Ryūkyū islands.

The Allied countries were China, the United States, the United Kingdom (and its colonial India), Australia, the Philippines, the Netherlands, and New Zealand. Japan was facing them.

The battle of Okinawa, whose code name was Operation Iceberg, was the biggest battle of the Pacific War. It lasted 82 days, from the beginning of April to the middle of June 1945. The battle has been called Steel Typhoon or Steel Rain because of the ferocity of the attacks.

The conquest of this island was a key to initiate the attack on the mainland of Japan. The Allies used Okinawa as a base for air operations under the plan to invade Japanese territory, codenamed Operation Downfall.

A. Guam  

B. Iwo Jima  

C. Okinawa  

D. Sakhalin.

Explanation:

Although some insignificant groundings happened later, the last significant amphibious incursion of a Japanese Island got the place through the Conflict of Okinawa, which was upheld between American GIs and Japanese warriors. It was a remarkably harmful combat with 94% of the 110,000+ Japanese guardians drowning. The Allied failures were also great at about 25,000+ lifeless. The encounter took place from April 1 - June 26, 1945. The greatest death rates and the determination of the guardians to last struggling profoundly influenced the US Military High Command’s conclusion to drop the atomic bombs on mainland Japan rather of originating an aggression.

i would go with the last one

with my recent question