Need help please. It's urgent. How do the sound effects enhance this passage? Lin was satisfied but exhausted from her day. She carried her camping and hiking gear all the way up the mountain with her troop. She swam in the hot springs and cooked her two meals on an open fire she helped prepare. This certainly was a different pace than living in the city. It was just as noisy as the city, but in a different way. She could hear crickets chirping, small animals rustling, and the crackling of the glowing camp fire.

How do the sound effects enhance this passage?
a) They add to the exhausting mood of Lin and the troop's journey.
b) They add more meaning to what it sounded like from inside the tent.
c) They contribute to the depressing mood of camping outside.
d) They contribute to the beauty of the city, where Lin lived.
Note: I confuse between c & d)give me an opinion...Thank you.