To date, what has most propelled the digital revolution? A. Multimedia advertising
B. Social networking sites
C. Desktop computers
D. Cellular phone calls

The answer is Computer Networks. The development that has contributed most to the digital revolution is the Computer Networks. The Digital Revolution refers to the advancement of technology from analog electronic and mechanical devices to the digital technology which we have today. So it's B because computer networks is a social networking site

it would be a. excessive network collisions or d. slow connectivity between devices those would be my answer.