According to the passage, the LRCWA's report recommended that contingency-fee agreements

The "correct" answer is almost identical to another incorrect answer. If the reason that C is incorrect is that reasonably happy could still not be as happy as someone without pets then saying someone is happier because they have pets is essentially saying that this one thing makes them happier, but does not specify that they are happier than people without pets. E on the other hand expresses that people who do not have pets experience being unhappy which is a direct contradiction of the cause-effect relationship from the passage. If the person who does not have a pet is unhappy then they are not as happy as possible, which would be all the time.