When variables are used as tokens,what is the correct format if the variable name is Test Variable? DCO versions are used to:

DCO (Dynamic Creative Optimization) versions are used to tailor creative elements to specific target audiences. This means that different versions of an ad can be automatically generated and served based on various audience attributes like demographics, interests, or past behavior. The goal is to maximize ad relevance and performance by showing the most impactful creative to each user segment. Serving In-Stream and Banner formats simultaneously is a function of ad serving capabilities, not DCO versions. While DCO can be used for both In-Stream and Banner ads, its core purpose is dynamic content customization based on audience targeting.