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.
1.) <span>Because proctor doesn't have any proof of the affair and no witnesses were around
2.) </span><span>Because she wants him to be honest and tell the truth
3.)</span><span>Because he had an affair with Abigail and got caught/ their marriage is going downhill because he hasn't gone to make an attempt to end it</span>