Final answer:
The correct answer to fill in the blanks is C. yourself, yourself, which uses a reflexive pronoun to indicate that the subject is also receiving the action.
Step-by-step explanation:
The correct answer is C. yourself, yourself. In the given sentence, the first blank requires a reflexive pronoun to indicate that the 'you' in question is the receiver of the action. The second blank re-emphasizes the point by indicating the same party (you) will be in possession of the decision-making process, thus the reflexive pronoun is used again. The complete sentence appropriately reads: 'You have agreed to the terms and conditions laid out by the institution, and now there's nothing you can do about yourself, yourself.'