Answer:
The correct answer is A. Lincoln gave his "A House Divided" speech while running for the U.S. Senate.
Step-by-step explanation:
The House Divided speech was delivered by Abraham Lincoln on June 16, 1858, in Springfield, by accepting the nomination of the Illinois Republican Party to run for the Senate. The speech became the basis of his campaign against Stephen A. Douglas, with whom he debated before the election, and by whom he was ultimately defeated in the Senate race. In saying that "a house divided against itself can not remain", Lincoln was referring to the division of the United States into free and slave states.