To make a strong argument, the writer or speaker must avoid logical fallacies.
This is because a fallacy is something that is untrue, thus if it was logical your reader might be persuaded against your argument. Basically, as a writer you don't want to contradict yourself and you only want to support one side of an argument.
Hope this helps! :)
Answer:
It features a comma splice.
Answer:
Students who study music fare much better than those who do not.
American History is studying the American colonies.
The answer to your question is A) Therefore.