Which of these statements is true regarding Appian applications?

The statement that you can reuse objects across different applications is accurate. In Appian, the design encourages modularity and reusability, which allows developers to use existing components such as interfaces, processes, and rules in multiple applications. This capability not only enhances efficiency by saving development time but also ensures consistency across applications, as the same objects will function uniformly in various contexts. This reinforces best practices in application development and promotes a streamlined approach to managing and updating shared resources.

The other statements do not accurately describe the capabilities of Appian applications. Applications can share data through various means, allowing for greater collaboration and integration. While applications may use different objects, they do not all need to be created from scratch, as existing components can be leveraged. Additionally, applications exist within a broader ecosystem where resource sharing and interaction are common, countering the notion that each application is entirely isolated from others.