World War I included armed conflict in all of the following areas except?

"John", you are partially wrong. The fighting was by Australian soldiers attacking several locations in "New Guinea" (German New Guinea) which later became an Australian Protectorate under the "League of Nations" and later became joined with Papua to become Papua New Guinea.

Yes, the Brits did take over some German territory in China but there was no fighting involved that I know about and the Japanese annexed some other German territories in China.. Neither battles and annexations are listed in any of the internet sites I looked at.

I too, believed the answer was South America, but there was a "Battle of the Falklands", so South America is wrong.

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The answer is that all A, B, C, and D are areas where there were battles.

B. Armed conflict took place in all other areas listed. China, Vietnam, Korea and Japan managed to stay out of this one, although Japan was aligned with the Allies during this war, and Vietnam, as part of the French Empire, contributed soldiers for action elsewhere.

The actions I would attribute to South America actually took place at sea in that area. I know of incidents in which German U-Boat crews were interned in South American countries. This might not meet the full criteria for armed conflict.

There was actually a small bit of conflict in East Asia, the Brits did do some attacking on some German colonies with the help of Japan although it didn't last very long. I'm going to say South America.