Lightheartedness means cheerful, carefree ect.
This means the line "The sounds of water splashing and laughter echoed in the distance; Tim's friend's had gone for a late-night swim." is the phrase that is the correct answer, since it talks about the happy actions of Tim's friends.
Answer C.
It might be stated that Mill employed a combination of formal and informal tone in "On liberty..", by developing some complex ideas, meanings and expressions. The author used metaphors and figurative languages to appeal to the audience. It might be added that Mill wrote those who agreed with him and he discussed his thesis by attacking the conservatives.
He used frases such as <span> "no one's idea," "no one should assert," "it would be absurd," "nobody denies" . </span>
I believe the answer is Person vs. Person
