To solve this question, the user needs to have knowledge about security concerns related to programming languages.

Authentication and session management are security concerns that are relevant to web applications. They ensure that users are who they claim to be and that the information stored on the server is secure.

Now, let's go through each option and explain why it is right or wrong:

A. Java: This option is correct. Java is a popular programming language for web applications, and it has built-in features for authentication and session management. Java web applications use a session ID to identify each user's session, and the server uses this ID to retrieve the user's session data.

B. .NET: This option is also correct. .NET is a framework for building web applications, and it includes features for authentication and session management. .NET web applications use cookies to store session information, and the server retrieves this information using the session ID in the cookie.

C. Managed Code: This option is too broad to be correct or incorrect. Managed code refers to code that is executed by a runtime environment, such as Java or .NET. While both Java and .NET use managed code, this option does not specify which language or framework is being referred to.

D. C: This option is incorrect. C is a programming language that is not commonly used for web applications, and it does not have built-in features for authentication and session management. While it is possible to implement these features in C, it would require more manual coding than using a language like Java or .NET.

The Answer is: A or B