The correct answer is B. North Korean forces invaded South Korea.
Explanation:
The Korean War was a conflict between Nort Korea that was supported by the Soviet Union and China and South Korea that was supported by the U.S in which each side wanted to take control of all the Korean territory. This conflict began on June 25th of 1950 as the forces of North Korean invaded South Korea as the military forces crossed the border and ended on July 27th of 1953 as an agreement between both sides was signed and a Demilitarized Zone was created between North Korea and South Korea. Therefore, the event that started the Korean War was North Korean forces invaded South Korea.
