What must be done to avoid plagiarism when including a direct quotation in a research paper?
the source must be about the same topic.
the source must be properly cited.
the content must be rephrased.
the content must be free of bias.

The source must be properly cited.

Explanation:

If the source is not properly cited, it can be considered plagiarized work.

the influence of charles louis de secondant , baton montesquieu.

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