What is the best description of Buck‘s character, based on this excerpt? Buck is willing to compromise morality for survival.
Buck is a prankster who enjoys teasing his teammates.
Buck is a bully who taunts the weaker pack members.
Buck is eager to entertain the pack with his tricks.

Buck is willing to compromise morality for survival

Excerpt (you forgot to include it in your question):

To remedy this, [Buck] ate as fast as they; and, so greatly did hunger compel him, he was not above taking what did not belong to him. He watched and learned. When he saw Pike, one of the new dogs, a clever malingerer and thief, slyly steal a slice of bacon when Perrault's back was turned, he duplicated the performance the following day, getting away with the whole chunk. A great uproar was raised, but he was unsuspected; while Dub, an awkward blunderer who was always getting caught, was punished for Buck's misdeed.

answer: may i ask who shelly is?