cellular networks use digital signals and can transmit voice and data at different speeds based on how fast the user is moving; it supports video, web browsing, and instant messaging

true never assume something it makes an a** out of u and me.

answerstandard;

the answer is b. executive summary. a management summary, or executive summary, is a short article or section of a document, produced for business purposes, that condenses a longer report or proposal or a group of related reports in such a way that readers can rapidly become familiar with a large body of material without having to read it all.