In which war did america experience a direct military attack upon its own territory? a) world war i b) world war ii c) the vietnam war d) all of the above

b) World War II

And said "attack" is most likely referring to Pearl Harbor.

In this war, America experienced a direct military attack upon its own territory and this war was the world war 2. So the answer would be the second option. This war attacked the Pearl Harbor and made a huge historical damage in all over the world and causes all countries' economy to degrade.