The utilities V1 and V2 are ( ) quantities. A: Unobserved B: Unestimated C: Observed D: Predicted

What is the finding of the new study? A: Teenagers’ lifestyles have changed greatly in recent years. B: Many teenagers resort to drugs or alcohol for mental relief. C: Teenagers experiencing psychological problems tend to use a lot of media. D: Many hitherto unobserved youngsters may have psychological problems.

What is the finding of the new study? 未知类型：{'label': 'questionDesc', 'content': '请根据材料选择正确答案。', 'isMemberControl': 0, 'type': 181} 未知类型：{'label': 'source', 'content': '2016年12月 六级 卷一 仔细阅读2', 'isMemberControl': 0, 'type': 181} A: Teenagers’ lifestyles have changed greatly in recent years. B: Many teenagers resort to drugs or alcohol for mental relief. C: Teenagers experiencing psychological problems tend to use a lot of media. D: Many hitherto unobserved youngsters may have psychological problems.