Focuswhy did japan invade manchuria in 1931?

What is the most necessary information that happened in the titanic movie

The holocaust of world war ii resulted in a) the nazis effectively used propaganda to gain and hold power in germany. b) ethnic regimes carried out mass devastation. c) deporting all european jews to the island of madagascar. d) the systematic mass slaughter of european jews and and others in nazi concentration camps during world war ii.

What country aided north korea in the korean war?