Final answer:
Option C reflects the theme that appearances can be deceiving, as Bruno's final jump in the race defies the colony's expectations and demonstrates that one's abilities are not solely determined by their physical appearance.
Step-by-step explanation:
The author uses the character of Bruno in the race to illustrate that one shouldn't judge others based on their appearance. Among the presented options, choice C, "Bruno used the last jump to show the colony that he could win the race, despite his size," most effectively embodies this theme.
As the motif aligns with the classic fable The Hare and the Tortoise, where the slow but steady tortoise wins the race, it suggests that despite assumptions about someone's capabilities based on their physical attributes, their actual performance may defy these preconceptions. Option C reflects the message that determination and ability can overcome expectations set by outward appearance.