A

　　When you’re on the go, your best friend and resource can be your phone. In the age of smart phones, apps are like guiding stars：They can point you in the right direction for a hotel, list expenses, send postcards, and much more. When used together, these apps can be the basic travel tool, placing a wealth of information at your fingertips no matter where you are on the planet. U.S. News Travel has picked the essential travel apps, known for their utility and reliability. Best of all, they cost absolutely nothing.

　　Trip It

　　Your Personal Travel Agent

　　Be your own travel agent and plan every detail of your trip—from car rental to accomadating restaurants—with Trip It. You can make travel schedule by hand, or simply forward the email confirmations of your flight, rental car, train tickets, and hotels to plans.

　　Weather Free

　　Your Go-To Meteorologist(气象学者)

　　Stop trying to explain the weather forecast on the evening news (particularly when it’s in a foreign language). The Weather Free app informs you (in English) of the 　　climate in various locations. It features the local weather, and other key factors that will inform your decision about what to wear before stepping outside.

　　Goby

　　Your Event Guru

　　When you’re in a foreign city, you sometimes look around and ask：Where are all the people？ Goby has the answer. This app pinpoints the neighborhood hot spots (including museums, hotels, eateries, and more) in your neighborhood. But its true value comes in finding nearby events. You’ll discover concerts, plays, and more right around the corner.

21．What is the advantage of using travel apps picked by the U.S. News Travel？

A．They can solve any problem you come across.

B．They reduce your travel budget.

C．They exercise your fingertips.

D．They are reliable and free of charge.

22．With the help of the travel apps used together, travelers can do the following things EXCEPT __________.

A．rent a car

B．decide what to wear

C．look for a friend while traveling

D．find the nearby museums

23．Where are the readers likely to read the passage above？

A．In a geography textbook

B．In a science and technology magazine

C．On a popular website

D．In a business report