Read this line from the text: The American people in their righteous might will win through to absolute victory This text implies that Roosevelt believed he had successfully argued the case to go to war Roosevelt believed those who had been unjustly attacked would triumph Roosevelt had cause to doubt Americans' willingness to enter into war Roosevelt had to convince Americans of the likelihood that a war could be won

The correct answer is B.

This speech was given after the attack on Pearl Harbor during World War II. During this attack, the United States was unjustly attacked.

With these words, Roosevelt is saying that the United States, which had been unjustly attacked, will win through to absolute victory.

He does not have to convince Americans that a war could be won, because, as he said, " The people of the United States have already formed their opinions and well understand the implications to the very life and safety of our nation."

Therefore, the correct answer is Roosevelt believed those who had been unjustly attacked would triumph.