Answer:
Following is the true statement about the attitude of US senators in 1920:
D) They opposed entry into the League of Nations and refused to ratify the Versailles Treaty.
Step-by-step explanation:
The US senate, for the first time in 1919, rejected a peace treaty. The main reason put forth by the US senators was that USA was giving up too much power under the League of Nations, and it would be like surrendering and forfeiting. The senate reconsidered the treaty under reservations in 1920, which again couldn't get the two-third majority votes. Hence, the USA never ratified the Treaty of Versailles, nor did it join the League of Nations