Seudónimo Seudónimo 21-09-2020 Social Studies contestada After the first day of fighting at Gettysburg, the arrival of reinforcements allowed✖ the Union to avoid more casualties.✔ the Union to hold the line and win.✖ the Confederacy to break the lines.✖ the Confederacy time to regroup.In conclusion, the answer is B.(I am doing this for the people that come across this question and didn't know the answer.){hope this helped}btw this is a question in the unit test review for grade 7 in the semester a for unit 4.