Final answer:
The quote that best represents Tarzan's determination is when he sets out alone early in the morning on his quest, showing his proactive and focused nature.
Step-by-step explanation:
The quote from Passage 1 that best highlights Tarzan's determination is B) "So, early one morning, he set forth alone upon his quest." This illustrates Tarzan's proactive approach and his resolve to undertake his quest independently, without hesitation or delay. It conveys a sense of urgency and focus on his goal, showcasing his determination to follow through on his plans.