Comrades hope I was helpfull
Answer: The topic is the general subject of a paragraph or essay. Topics are simple and are described with just a word or a phrase. The main idea is a complete sentence; it includes the topic and what the author wants to say about it. If the author states the main idea in his paragraph it is called a “topic sentence.”
Explanation:
If I remember correctly it's A.
Characters affect theme in terms of conflict and dilemma. If a conflict or dilemma of a given story was altered then the story would take a changed path. Therefore, there would be alteration in the actions of the characters which at the same time would transform the plot of the story.