Which of the following is true of "click" fraud?

A) The click-on process functions only in online contracts and not for online advertisements.
B) Clicks are proven ways to gauge interest in the advertiser's service or product.
C) A problem that arises in this area is verifying the identity of the "clicker."
D) The click-on process functions only for online advertisements and not for online contracts.

Click fraud is a problem in online advertising, where individuals or automated programs fraudulently click on ads to drive up costs for advertisers. One of the challenges in detecting and preventing click fraud is verifying the identity of the clicker, as it can be difficult to distinguish between legitimate clicks and fraudulent ones. Option A and D are incorrect because the click-on process can be used for both online contracts and online advertisements. Option B is incorrect because while clicks can indicate interest, they can also be manipulated through click fraud, making them an unreliable measure of genuine interest.