根据以下材料，回答21-35题
The number of speakers of English in Shakespeare´s time is estimated to have been about five million. Today it is estimated that some 260 million people speak itas a (an) 21 language, mainly in the United States, Canada, Great Britain, Ireland, South Africa, Australia and New Zealand. In addition to the standard varieties of English found inthese areas,22 are a great many regional and social varieties of the language as well as 23 levels of usage that are employed both in its spoken and written forms.
In fact, it is 24 to estimate the number of people in the world who have acquired an adequate working knowledge of English in addition to their own languages. The 25 for English learning and the situations in which such learning takes place are so varied that it is 26 to explain and still more difficult to judge 27 forms an adequateworking knowledge for each situation.
The main reason forthe widespread 28 for English is its present day importance as a world language. Besides 29 the indefinite needs of its native speakers, English is a language in which some of important works inscience,technology,and other 30 are being produced and not always by native speakers. It is widely used for 31 purposes as meteorological( 气象的)and airport communications,international conferences,and the 32 of information over the radio and television networks of many 33. It is a language of wider communication for a number of developing countries, specially former Britishcolonies. Many of these countries have multilingual 34. and need a language for internal communication in such matters as government, commerce, industry,, law and 35 as well as for international communication and for entrance to the scientific and technological developments in the West.
第25题答案是（　　）

A purpose     

B cause       

C effect       

D method