A developer created a landing page in CloudPages which return unique content when subscriber data is located on a related data extension. The developer does not know if all subscribers have rows in the related data extension, and want default content to render if no subscriber data is found on the related data extension. Which best practice should the developer follow to control the unique and default content?

NTO wants to exclude sends to specific subscribers based on a business rule, which is defined in an Exclusion Script. Which three types of sends would support this functionality? Choose 3

A developer wants to design a custom subscription center in CloudPages. The developer prefers to code in AMPscript, but is also skilled in Server-Side JavaScript. While the developer is confident their code is of high quality, they would still like to handle unexprected errors gracefully to ensure the best user experience. Which feature should handle this scenario?

A developer identified a use case where a triggered send of an email is needed. The developer already successfully set up authentication with a Client ID and Client Secret has used them in several REST calls. When the REST call is made, a "401 Unauthorized" error is returned. What is the first thing the developer should check?

A developer wants to build an email that dynamically populates the physical address of a company's locations using the variable address. The deployment goes to millions of subscribers and the developer wants the fastest possible performance.
Which AMPscript solution should be recommended?