A．They have oceanfront hotels.

　　B．They are volcanic islands.

　　C．They are hard to reach.

　　D．They are in Brazil.

　　解析：选C　细节理解题。根据Baia do Sancho, Brazil部分中的"Getting there involves walking along steep, rocky cliffs and then climbing down a ladder"及Grace Bay, Turks and Caicos部分的"While Baia do Sancho is difficult to get to, Trip Advisor's second­ranked beach could not be much easier for tourists to reach"可知选C项。

　　22．Which is most suitable for sunset watchers?

　　A．Playa Paraiso.　　　　　　　 B．Eagle Beach.

　　C．Grace Bay. D．Siesta Key.

　　解析：选B　细节理解题。根据"Eagle Beach, Aruba部分中的"Eagle Beach may be best known, however, for its dramatic sunsets"可知选B项。

　　23．What can we learn from the text?

　　A．Dr. Beach named Baia do Sancho the best beach in the world.

　　B．Visitors can enjoy different sports on Paraiso's beach.

　　C．Visitors can find rare seashells at Siesta Key.

　　D．Cayo Largo is an island of Aruba.

　　解析：选C　细节理解题。根据Siesta Key, United States部分中的最后一句可知选C项。

　　B

　　(2018·河南省六校联考)In the age of the social network, there's definitely such a thing as sharing too much；when it comes to losing weight, sharing could be key, though.

　　A new Northwestern University study published in the Journal of the Royal Society Interface found that those who had an active hand in such online communities lost a higher percentage of their body weight compared to users who participated sparingly.

The researchers discovered that the users who recorded their weight and established