Which of the following is a run-on sentence? Its ice slab walls of thick stone lie dormant, awakening only to sing the organ’s echoing melodies that reached my apartment window on Sunday mornings.
The city center in the valley below holds a 13th century cathedral with piercing Gothic spires that stretch upwards toward the heavens.
From its towering position on a hill overlooking the valley, a castle fortress rests; this silent sentinel stands as a powerful reminder of the ancient kings and queens who ruled centuries past.
The melodies would blow through my window with the breeze their notes would bounce off the walls and ceiling.

Which sentences from part 1 of the call of the wild would best serve as evidence of the theme "sometimes survival depends on knowing when not to fight"? buck had accepted the rope with quiet dignity. to be sure, it was an unwonted performance: but he had learned to trust in men he knew, and to give them credit for a wisdom that outreached his own. he had merely intimated his displeasure, in his pride believing that to intimate was to command. but to his surprise the rope tightened around his neck, shutting off his breath. he saw, once for all, that he stood no chance against a man with a club. he had learned the lesson, and in all his after life he never forgot it. that had given them an unfair advantage; but now that it was off, he would show them. they would never get another rope around his neck.