Short Answer: A
A really super writer could get away with putting the thesis statement in the conclusion of a paragraph piece. But present day English Departments have become very rigid about where the thesis is.
It is always in the introduction. The idea is that you have to guide your reader to the arguments that follow in the paragraphs to come between the introduction and the conclusion.
I believe the answer to your question is true
I would say to entertain friends(D) because it is not professional enough for other options.
