Which one of what? You don't say the choices:)
To include interval training, find a steep hill or sets of stairs that will allow you to climb steadily for one to three minutes. Push as hard as you can going up, then recover coming down, and repeat for anywhere from 20–60 minutes depending on how close to your climb you are.
The answer to your question would be prohibited as it does mean to be forbidden or not allowed to and on this sentence is saying that since it was too noisy it was impossible to study.
The answer is B, Run-on sentence.