What is a major difference between a true demand-side platform (DSP) and an ad network?

The correct choice highlights a key distinction between a demand-side platform (DSP) and an ad network in their operational focus. A true DSP operates primarily on the demand side of the advertising ecosystem, focusing on automating the purchase of ad inventory on behalf of advertisers. Conversely, an ad network aggregates inventory from various publishers and sells it to advertisers, which means it deals with aspects of both the demand and supply sides. This dual focus allows ad networks to act as intermediaries, connecting buyers with a wide range of available inventory.

In contrast, a DSP generally connects directly with multiple supply sources, utilizing real-time bidding (RTB) to purchase inventory more efficiently and target specific audience segments based on complex algorithms and data analysis. This direct purchasing capability distinguishes DSPs from ad networks, which typically rely on partnerships with numerous publishers to manage inventory.

The other options presented do not accurately capture the primary difference between a DSP and an ad network, making the relative focus of operations the most significant distinction.