Which of the following might have been in direct conflict with the united states stance on isolationism at the onset of world war ii?

The most likely answer to this question is answer b, selling weapons to other countries. While the U.S claimed to the rest of the world that it was to remain neutral, it secretly sold weapons to Britain through the lend lease act

it was on the rise and doing very well and would continue to do well until the great depression from 1929-1939