The significance of Randall’s final thought, “At last, Randall felt like the lucky one,” is primarily captured by option C) He appreciates the friendships and family he has.
Throughout the narrative, Randall grapples with feelings of envy and inadequacy when comparing his life to Starks'. Initially, he views Starks as someone who has everything — wealth, popularity, and a celebrity father — while he perceives himself as lacking in both material possessions and social status. However, as the story unfolds, Randall comes to realize that despite the differences in their lives, the joy of genuine friendship and the warmth of family are far more valuable than material wealth.
The pivotal moment occurs during the impromptu birthday celebration for Starks at Randall’s house, where Randall's home is filled with laughter and camaraderie. This experience shifts his perspective, leading him to recognize the significance of meaningful connections over superficial status. Thus, the feeling of being "the lucky one" highlights his newfound appreciation for relationships and the supportive environment of his family and friends.