The Red Scare? If you list the options, then it would be clearer, but it should be anything dealing with the USSR and US due to McCarthy’s rise in power of knowing communist spies
Answer:
Dual occupation of Korea led to the Korean War
Explanation:
For the first answer, communism certainly did not strengthen Korea's economy.
For the second, China was already at war with Japan (who controlled Korea at the time) far before the Soviet Union ever got involved with the Pacific front.
For the third, the Japanese army only surrendered after the US dropped the second atomic bomb on Nagasaki.
Leaving only the fourth as the correct answer.