Here are the answers to your questions based on historical context:
Question 1: What was the “root issue” that prevented Congress from adding Texas to the U.S. for many years?
Answer: B) the issue of slavery
Question 2: Which of these Presidents was MOST responsible for making Texas a state?
Answer: C) Tyler
Question 3: The Mexican War effectively ended with the capture of __________.
Answer: D) Mexico City
Question 4: Which of these was part of the Treaty of Guadalupe Hidalgo?
Answer: B) US paid Mexico $15 million.
Feel free to ask for more information about these questions or any related topics!