Final answer:
Different digital advertising environments, such as connected TV and desktop, or desktop and mobile apps, typically require separate advertising line items due to technical and platform-specific constraints.
Step-by-step explanation:
The question relates to digital advertising environments, specifically asking about the compatibility of different inventory sources within a single advertising line item. Generally, in the digital advertising landscape, certain environments may not be able to run within the same line item due to technical, behavioral, or platform-specific constraints.
The environments and inventory sources that cannot run within a single line item are Connected TV and desktop. This means that if you want to run ads on Connected TVs and desktop devices, you would need to create separate line items for each of them. For example, if you want to run a video ad on Connected TVs and display ads on desktop devices, you would need two separate line items.
For instance, environments such as connected TV and desktop advertising would typically be separated into different line items to manage targeting, ad formats, and reporting effectively. Similarly, mixing desktop and mobile apps within a single line item could present challenges due to the differences in user behavior, ad delivery mechanisms, and tracking capabilities.