Answer:
The correct answer is: Obtain a waiver of documentation of informed consent.
Explanation:
Before such an experiment or study could take place, it is important to inform the subject about all kinds of consequences. The risks should be made clear and they should be able to sign documentation giving their complete consent on what is going on.
Apart from simple ethics, such documentation helps to legal separate the subject from people carrying out the experimentation which might be useful in worst-case scenarios.