請問哪項技術有助於廣告主放送同時適用於電腦和行動平台的廣告？

HTML5 is the correct answer because it is a versatile web technology that enables the creation of responsive and adaptive ad creatives. These ads can automatically adjust their layout and functionality to fit various screen sizes and devices, including desktops and mobile phones, ensuring a consistent user experience across platforms. Display & Video 360 Marketplace is incorrect because it is an ad exchange and platform for buying ad inventory, not a technology for creating cross-platform ad formats. Native applications are incorrect because they are standalone programs designed for specific operating systems (iOS or Android) and are not inherently cross-platform for ad delivery in a browser context. Campaign Manager 360 is incorrect because it is an ad server and campaign management platform, used for trafficking and reporting, but not for the creation of the ad creative itself.