Soon, more of the information we receive via the Internet could come (155) in digital wrappers.
Wrappers are made up, (156) software code that’s targeted to do specific things with the data (157) within them, such as helping to define queries for search engines. They also keep (158) from (159) access to that code.

A．gain

B．gained

C．gains

D．gaining

平均数反映了（）。

A、总体分布的集中趋势

B、总体变动的趋势

C、总体分布的离散趋势

D、总体中总体单位分布的集中趋势