What is a key characteristic of embedded content or iFrames in Salesforce?

The key characteristic of embedded content or iFrames in Salesforce is that it requires the user to wait for asynchronous loading. This means that when an iFrame is loaded, it does so independently of the main page content. The main Salesforce page continues to load while the content within the iFrame is fetched asynchronously. This approach allows developers to embed external web pages or applications without blocking the main user interface, thereby improving the overall user experience by making the application feel more responsive.

While other options might touch on different aspects of data retrieval or usage, they do not accurately capture the primary behavior of iFrames regarding loading processes. Although synchronous data retrieval may seem advantageous in some contexts, it does not apply to iFrames, which inherently function asynchronously. Additionally, the claim that iFrames can only reference URLs without parameters is inaccurate, as they can accept various parameters within the URL. Lastly, iFrames do not directly retrieve data from the Salesforce database; rather, they display content from external sources, which may or may not interact with Salesforce data through APIs.