III. Reading comprehension: 2% for each, 30% in total. 
(A)        When one thinks of language, the thousands of different tongues spoken in the world may come to mind. However, the humanvoice cannot travel very far. In remote regions, such as thick forests and mountains, whistling is used instead to communicate acrosslong distances. One may think of herders whistling fervently, sending their messages across ravines. It is also found in Star Wars,particularly when R2-D2 whistles to other droids. However, the best-studied whistled language is Silbo Gomero, which is found on oneof the Canary Islands called La Gomera.       First used by the island’s inhabitants as an ancient language of the Canaries, Silbo Gomero, or simply Silbo, became the whistledform of Spanish after settlers arrived in the 16th century. Since there are only four consonants and two to four vowels of Silbo, wellversed silbadores, or whistlers, depend on deduction skills to understand each other. Usage decreased in the 1950s due to a growingsystem of roads, economic decline, and the development of telephones. To combat this, the government of the Canary Islands beganan initiative to preserve Silbo in the 1990s by teaching it as a required subject in elementary school. In 2009, UNESCO added SilboGomero to its list of Masterpieces of the Oral and Intangible Heritage of Humanity, ensuring its survival.      Another well-known whistled language exists in a village nestled in the mountains of northern Turkey called the “Village of theBirds,” or Kuskoy. Though the language is dying, as gossip is best shared by phone, whistled Turkish is interestingly processed usingboth hemispheres of the brain while spoken languages, even Silbo, are typically processed in the left hemisphere. It may be a pipedream, but this research is a glimmer of hope for stroke victims who may learn to communicate through whistles.
【題組】21. ( ) Which kind of topography isn’t mentioned in the article for the existence of the whistled language?
(A) Mountains.
(B) Ravines.
(C)Forests.
(D)Glaciers.