Questions 46 to 50 are based on the following passage.-|||-You may know the feeling.It's the late afternoon,and you still haven't left the house. You've spent the last-|||-several hours on your phone,scrolling through your Facebook news feed,refreshing Twitter and watching YouTube-|||-videos.Asmartphone might feel like it's keeping you connected,but it can also be a way of secluding yourself.-|||-Data from a recent study conducted by researchers at Northwestern University's Feinberg School of Medicine-|||-found that the scenariodescribed above-high volume of phone use and a static(静止的)geographic location-could-|||-be linked to depression.The study,published in The Journal of Medical Internet Research,also found that depressed-|||-people,on average,spend more time on the phone than non-depressed people-|||-"People are likely,when on their phones,to avoid thinking about things that are troubling,painful feelings or-|||-difficult relationshps David Mohr,one of the study's senior authors and a professor of behavioral psychology at-|||-Northwestern,in a statement."It's an avoidance behavior we see in depression."Mohr also pointed out that depressed-|||-people tend to withdraw emotionally and avoid going out-behaviors that are arguably facilitated by the constant-|||-entertainment stream avai on smartphones.-|||-The study's participants consisted of a mix of people with and without prior depression. They completed a-|||-questionnairedescribing t symptoms before agreeing to have their phone use monitored for two weeks.Using GPS,-|||-the researchers tracked their location and the amount of time they spent on the phone.They were then able to identify-|||-which participants were depressed using the aggregated phone data,with 87 percent accuracy.-|||-Sohrob Saeb, a research fellow at Northwestern,said in the release that phones could be more reliable for-|||-diagnosing depression tha traditional methods.In standard industry practic patients are often asked to describe-|||-their symptoms by indicating how sad they are on a scale of 1 to 10.According to Saeb,the release reported,these-|||-responses can be rote and unreliable.In contrast,the study found,a smartphone can unobtrusiv (不引人注目地)-|||-and accurately measure a patient's daily activity,providing data that could trigger a health care provider to recognize-|||-the need for an intervention.-|||-46.What is the author's opinion about using a smartphone?-|||-A)It is only a tool to contact people.-|||-B)It makes people feel lonely.-|||-C)It does great harm to health.-|||-D)It keeps people apart from others.-|||-47.What can be learned from the study conducted by researchers at Northwestern University?-|||-A)Too much time spent on phones leads to depression.-|||-B)Depressed people tend to spend more time on phones than others.-|||-C)Spending more time on phones can help cure depression.-|||-D)Non-depressed people spend little time on their phones.-|||-48.According to Mohr,why do depressed people focus on phones?-|||-A)They tend to temporaraly forget about unhappiness.-|||-B)They feel entertained and amused by phones.-|||-C)They do not have many friends to hang out with.-|||-D)They find confidence and happiness from the phones.-|||-49.What do we know about traditional methods for diagnosing depression?-|||-A)Patients'location is monitored by GPS.-|||-B)Patients describe their symptoms in words.-|||-C)Patients complete a questionnaire to describe symptoms.-|||-D)Patients indicate their sadness on a scale of 1 to 10-|||-50.Patients'daily activities can be measured by smartphones so that __ -.-|||-A)they can adjust their living habits if necessary-|||-B)their family and friends can know them better-|||-C)they can get timely health care if needed-|||-D)they will do their best under the monitoring