Even offline, the 18-year-old handles criticism more gracefully than many folks twice her age. What motivates it? In an Instagram response to Giuliana Rancic's apology for her tone-deaf joke about Zendaya's 2015 Oscars hairstyle, she invoked Martin Luther King Jr. in emphasizing her commitment to elevating pop cultural conversations above prejudice, misogyny, and body-shaming."Let's be that light and spread that love," she wrote.Somebody give this woman a PhD in clapping back, already.