Answer :
The answer to the question "Which of the following would prevent Japanese intervention in its neighboring island of the Philippines?" The answer is D. The Treaty of Portsmouth; once WW2 ended, the Treaty of Manila established the independent nation of The Philippines, preventing any future intervention from Japan. The Gentlemans Agreement, would not have any legal standing; The Roosevelt Corollary was dealing with the US's involvement with Venezuela; The Root-Takahira Agreement was one between US and Japan; and the Teller Amendment were conditions on the US military in Cuba.