Answer: The right answer is the C) The source is biased because of its association with a campaign.
Explanation: Just to elaborate a little on the answer it can be added that, since the same person who wrote the source - an article about the harmful effect of fracking in the environment - also founded a campaign against fracking, and the research is on the topic of fracking (presumably on its pros and cons), it can certainly be inferred that the source will be biased, subjective and partial, since the author has publicly campaigned against fracking.
