Final answer:
Jeannette Rankin was indeed the first woman elected to the US Congress in 1917, representing Montana, and is recognized for her suffrage activism and pacifism. Hence, option (a) true is correct.
Step-by-step explanation:
Jeannette Rankin from the state of Montana was indeed the first woman to be elected to the US Congress. Jeannette Rankin, a field worker for the National American Women's Suffrage Association, played a significant role in achieving victories for women's suffrage in North Dakota and Montana. After her efforts, she made history by becoming the first female member of Congress in 1917.
Rankin was well-known not just for her pioneering electoral success, but also for her pacifist beliefs, notably opposing the US entry into World War I. Her courageous vote against the war, in line with her pacifist convictions, was a remarkable stance that ultimately cost her reelection. Rankin's legacy as an activist and as the first woman in Congress is a notable part of American history.