What is the most important reason for citing a source when quoting it directly?

So you don't plagiarize, because that's illegal. Also, so whoever's reading knows where you got it from so they can go there and read it themselves.

fearing kabuki could corrupt the nation’s morals, japanese government officials

explanation:

the national morals was so the japanese and the kabuki would stop fighting

nations must cooperate to bring about and maintain world peace.

nations must not wage wars or commit war crimes in a desire to control other nations.

i think i know which options you have but if these aren't options let me know