[求助]大全-5-19

19.   Recent estimates predict that between 1982 and 1995 the greatest increase in the number of people employed will be in the category of low-paying service occupations. This category, however, will not increase its share of total employment, whereas the category of high-paying service occupations will increase its share.

If the estimates above are accurate, which of the following conclusions can be drawn?

(A) In 1982 more people were working in low-paying service occupations than were working in high-paying service occupations.

(B) In 1995 more people will be working in high-paying service occupations than will be working in low-paying service occupations.

(C) Nonservice occupations will account for the same share of total employment in 1995 as in 1982.

(D) Many of the people who were working in low-paying service occupations in 1982 will be working in high-paying service occupations by 1995.（A）

               (E) The rate of growth for low-paying service occupations will be greater than the overall rate of employment growth between 1982 and 1995.

为什么答案是A，这个数学推理关系是什么样的呢？

着急，求教各位大牛