参考答案：Y

解析：第五段最后二句话指出“…but at least mention to a friend or family member where you’re going and when you expect to be back．For the price of a phone call，you can keep getting lost from becoming a permanent disappearance．”至少要告诉朋友和家人你要去哪里，什么时候会回来，这样你就不至于长时间的不在，而他们又找不到你，题干表达的意思与原文正好一致，因此答案正确。