Would "i think" be a complete sentence?

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.

Match the definition to the word for a better understanding of the paragraph. 1 money does not buy happiness or security. 2john ringling, one of the five brothers of the ringling brothers circus, started out in 1884 with a trained horse and a performing bear. 3for over forty years, he worked hard at the family enterprise, bought up smaller circuses, and imported new acts. 4in the 1920s, he was rated as one of the world's wealthiest men and owned every sizable circus in the country. 5over 5,000 people were on his payroll, and over 240 railroad cars were in his retinue each time the circus moved. 6at the time of his death, however, he was a nervous, unhappy man; he was also bankrupt and beset by lawsuits. 7his carefully built circus empire passed into alien hands. 8all those years of work had turned to dust. 1. business organization alien 2. group beset 3. without funds to pay debts retinue 4. troubled or harassed enterprise 5. strange; belonging to another person, place, country, or thing bankrupt

Need some on this. which answer is it?