"To come all that way, rifle in hand, with two thousand people marching at my heels, and then to trail feebly away, having done nothing—no, that was impossible."

What purpose does the end phrase separated by the em dash serve in this sentence?
Edit: The correct answer is "The phrase is meant to simplify and clarify the author's first thought." I'm 100% sure got full points for it on quiz.
For points just answer with "C. The phrase is meant to simplify and clarify the author's first thought."

in the spreadsheet, click on a cell, then type the numbers or text you want and press enter or tab. to write data to a new line within a cell, press alt + enter. to enter the same data in several cells at the same time you must select the cells in which you want to enter the same data, in the active cell write the data and press ctrl + enter.

tuttifroot

the quote relates to no dogs barked because the father and son learn a lot from each other. the theme is love because the father misses his son and they are trying to get to his mom where her dogs are barking.

the very first one i did this and passed the test with 5 wrong

the correct answer should be a