How Do Electronic Display Panels Most Likely Benefit an Advertiser

How do electronic display panels most likely benefit an advertiser?

A) Only the advertiser can change the display.
B) They are an inexpensive and flexible medium.
C) Their ability to eliminate selective perception makes their high costs worthwhile.
D) The transit authority must pay a premium price for the displays.
E) They are one of the oldest and most accepted forms of advertising.