One Disadvantage of Using the Internet as an Advertising Medium

One disadvantage of using the Internet as an advertising medium is

A) as a relatively new medium,it has attracted limited use.
B) it is difficult to translate messages that can be used in social media networks like Facebook and Twitter.
C) the effectiveness of online advertising is still uncertain.
D) it often creates more traffic than a firm can actually handle.
E) pay-per-click search ads on Google are expensive and ineffective.