Which event led to the arrest and imprisonment of many National Women’s Party activists? starting a hunger strike
repeatedly picketing the White House
organizing a march in Washington, D. C.
lobbying Congress for gender equality

Repeatedly picketing the White House

Explanation:

The National Woman's Party was formed with the sole purpose of fighting for a passage of a constitutional amendment ensuring women's suffrage throughout the United States. The prominent leaders were Alice Paul and Lucy Burns.

Before, during and after the World War 1, most women in America and many other parts of were disenfranchized. Despite the fact that the American President then Woodrow Wilson, a Democrat, championed democracy in the world during the wartime, the disenfranchizement of women in America was seen by the National Woman's Party as hypocrisy on his part. Therefore, the group started picketing the White House from between January 10, 1917 until June 1919. These protest group known as the Silent Sentinels were tolerated at first, but were subsequently arrested by police for obstructing traffic when they continued their picketing after the United States declared war in 1917.

faulty parallelism is a construction in which two or more parts of a sentence are equivalent in meaning but not grammatically similar in form.

the correct version of this faulty parallelism in the sentence is:

the hikers knew that the hike was six miles, that it usually required the entire day, and it would not be wise to start after 10: 00 a.m.

the problem is the last sentence, the first two have a basic subject+verb+object structure.

so, to give a proper balance to the structure, or better said, to give a parallel structure, we must write a basic s+v+o structure in all three sentences:

the hikers knew that the hike was six miles, that it usually required the entire day, and it would not be wise to start after 10: 00 a.m.

same test same problem