請依下文回答第 46 題至第 50 題：
 In the four minutes it probably takes to read this review, you will have logged exactly half the time the average 15- to 24-year-old now spends reading each day. That is, if you even bother to finish. If you are perusing this on the Internet,the big block of text below probably seems daunting, maybe even boring. Who has the time? Such is the kind of recklessly distracted impatience that makes Mark Bauerlein fear for his country. “As of 2008,” the 49-year-old professor of English at Emory University writes in “The Dumbest Generation,” “the intellectual future of the United States looks dim.”The way Bauerlein sees it, something new and disastrous has happened to America’s youth with the arrival of the instant gratification go-go-go digital age. The result is, essentially, a collective loss of context and history. The problem is that instead of using the Web to learn about the world, young people mostly use it to gossip about each other and follow pop culture, relentlessly keeping up with the ever-shifting linguafranca of being cool in school. Social life is a powerful temptation and most teenagers feel the pain of missing out.
And all this feeds on itself. Increasingly disconnected from the “adult” world of tradition, culture, history, context and the ability to sit down for more than five minutes with a book, today’s digital generation is becoming insulated in its ownstultifying cocoon of bad spelling, civic illiteracy and endless postings that hopelessly confuse triviality with transcendence.
At fault is not just technology but also a newly indulgent attitude among parents, educators and other mentors, who,Bauerlein argues, lack the courage to risk “being labeled a curmudgeon and a reactionary.”
【題組】 46 What is the main purpose of this passage?
(A) To cast doubt on the function of social media.
(B) To highlight the importance of history and politics.
(C) To praise transcendence over triviality.
(D) To point out an urgent issue American youths face.