Integration is the process of connecting and coordinating different components or systems to work together as a whole. In this scenario, the business is looking at extending the platform for an internally developed application using microservices from various cloud vendors. This means that the cloud architect needs to ensure that the microservices can communicate and interact with each other across different cloud platforms, as well as with the existing application. Integration is a critical requirement for the business to fulfill its requirements, as it affects the functionality, performance, and reliability of the application. Software, budgetary, and security are also important requirements, but they are not the most likely ones that the cloud architect needs to fulfill in this scenario. Software refers to the programs and applications that run on the cloud platforms. Budgetary refers to the costs and expenses associated with the cloud services and solutions. Security refers to the protection of the data and resources in the cloud environment from unauthorized access or attacks. References: CompTIA Cloud+ CV0-003 Certification Study Guide, Chapter 22, Microservices and Cloud Integration, page 3531.