求解一道Prep 2012的题！

elginlv

Surveys in Domorica indicate that only 10 percent of Domoricans in their twenties read a newspaper regularly, while more than half of all Domoricans over thirty read a newspaper regularly. Although Domoricans in their twenties constitute a large proportion of the population, newspaper publishers nonetheless predict that ten years from now, the percentage of Domoricans who regularly read a newspaper will probably be no lower than it is today.
　　

Which of the following, if true, provides the strongest grounds for the newspaper publishers’ prediction?
　　

A. The number of Domoricans in their twenties is less than the number of Domoricans over thirty.
　　

B. The number of newspapers in Domorica has been gradually increasing over the past several decades.
　　

C. The proportion of Domoricans in their twenties who regularly read a newspaper has always been low.
　　

D. The surveys defined a regular reader of a newspaper as someone who reads a newspaper more than twice a week.
　　

E. The proportion of Domoricans who regularly read a newspaper was higher 20 years ago than it is today.                                            
答案选C。我的问题是：我没懂答案的意思！文章可以理解，但是看不出文章与答案有什么关系。