The rising action in once upon a time begins when the wife fears that "people of another color" will "come up the street and tear off the plaque" that warns people to stay off their property and will "stream in" through their gates. The husband responds to her concerns by having electronically controlled gates installed.
The correct answer is B because a semi-colon is the best way to join the two sentences since they are both independent.
Hope this helps :)
The attitude an author has towards a particular subject is the mood.
