The answer to your question would be that the sentence that uses a verb in the subjunctive mood is the following one: If you were to score a touchdown at the football game, your team could win. That is, your answer would be D.
In English, the subjunctive mood is used to talk about conditional or imaginary situations. It is used to explore conditions that are contrary to fact. The selected sentence is an example of this use and also of the second conditional. It means that it is extremely unlikely for the person referred to to score a touchdown.