To answer this question, the user needs to know what session refers to in web development and the different ways in which session data can be stored.

In web development, session refers to a way of storing and maintaining user-specific data across multiple requests. This allows for a more personalized and customized user experience. Session data can be stored in different ways, including:

A. InProc: This option stores session data in memory on the web server. This is the default option in ASP.NET and is suitable for small-scale applications with a limited number of users. However, if the application is scaled up, this option may not be the best as it may lead to memory issues.

B. In State Server: This option stores session data in a separate process outside of the web server. This helps to reduce memory usage on the web server and allows for better scalability. However, it requires additional configuration and may impact performance.

C. In SQL Server: This option stores session data in a SQL Server database. This is a good option for large-scale applications with high traffic as it allows for better scalability and fault tolerance. However, it requires additional configuration and may impact performance.

D. None of the above: This option is incorrect as session data must be stored somewhere. If not in one of the above options, then it must be in a custom storage solution.

Therefore, the correct answer is:

The Answer is: A. InProc