What does CPA stand for in online advertising?

In online advertising, CPA refers to "Cost per action." This metric is crucial because it indicates how much an advertiser is willing to pay for a specific action to be completed by a user, such as making a purchase, signing up for a newsletter, or downloading an app.

The concept of CPA emphasizes performance-based advertising, where advertisers only incur costs when users take a desired action. This model enables advertisers to measure the efficiency and effectiveness of their campaigns more precisely. By focusing on actions that lead to conversions and measurable outcomes, advertisers can optimize their budgets and maximize their return on investment.

The other options reflect different concepts or are not standard terms used in online advertising, which is why they do not fit the definition of CPA.