How was U.S. policy toward France and Vietnam affected after communist North Korea invaded South Korea in June
1950?

Answer:
The United States decided to step up aid to the French in Indochina.
Explanation:
Only third option is correct as although United States weren't keen to participate in the colonial questions they realized that communist threat is rising.
Therefore, in May of 1950 US officially decided to help France in Indochina.
None of other options are correct.