What was the result of general macarthur's surprise attack on inchon?
the war ended shortly afterward.
the attack failed with many casualties.
north korea retreated north of the 38th parallel.
north korea fought back and took most of south korea.

North Korea fought back and took most of South Korea.

Explanation:

The Battle of Inchon was a major turning point in the Korean War, as it ended a string of victories by the North Koreans over the South Koreans. The North Korean forces were pursued beyond their limits, and the subsequent recapture of Seoul partially severed there supply lines in South Korea.

The operation involved some 75,000 troops and 261 naval vessels, and led to the recapture of the South Korean capital of Seoul two weeks later. The code name for the operation was Operation Chromite.

MacArthur argued that these factors would mean the North Koreans wouldn't expect the Allies to attempt an amphibious landing there.  Allied troops then converged on the North Korean army from the north and the south, killing or capturing thousands of enemy soldiers

its many islands, high mountains, and remote peninsulas isolated population centers.