A. what was the main issue in the treaty of versailles that the u. s. congress either all out rejected or had
reservations about? why?

On Nov 19, year1919, the senate rejected the treaty of Versailles based on primarily on the objections to the league of Nations. The U.S would never rectify the treaty to join the league of nations.

Explanation:

The "treaty of Versailles" was the formal peace treaty, their main enemy during the war was allies & Germany. It included a provision championed by "U.S. president Woodrow Willson" for the creation of an international body called the League of Nations.

The treaty was signed by the "representatives of each country in June 1919". For the U.S. to accept its conditions, however, it not be rectified by the congress, Senate majority leader "Henry Cabot Lodge a republican form Massachusetts", opposed the treaty, specifically the sections regarding the league of Nations. The war began in 1914 and ended in 1918, In four years 9 million people lost their lives & billions of dollars in the damage.

i really really really really really really dont know

both include an amendment process.