To answer this question, let's go through each option to understand why it is correct or incorrect:
Option A) An application layer will contain business logic - This option is correct because the application layer is responsible for implementing the business logic of an application. It handles the processing and manipulation of data to perform the specific tasks and functions required by the application.
Option B) An application layer manages connections to the database - This option is incorrect because managing connections to the database is typically handled by the data access layer or the database management system itself. The application layer interacts with the data access layer to retrieve or update data from the database, but it does not directly manage the connections.
Option C) An application layer can be distributed over many computers - This option is correct. In a distributed application architecture, the application layer can be divided into multiple components or services that run on different computers. This allows for scalability, fault-tolerance, and workload distribution.
Option D) Both a and b - This option is incorrect because option B is incorrect. The application layer does not manage connections to the database.
Option E) All of the above - This option is correct because both option A and option C are correct. The application layer contains business logic and can be distributed over many computers.
Therefore, the correct answer is E) All of the above.