Which of the following allows page information to be retained in a web application?

State management is a crucial concept in web applications that allows for the retention and management of user data and page information across different requests. Unlike traditional desktop applications, web applications are stateless, meaning that they do not retain user information or the current state between page requests unless explicitly managed.

State management techniques, such as session state, view state, and application state, enable developers to store user data temporarily or persistently. For instance, when a user fills out a form, state management can help retain that data even if the user navigates away from the page and then returns later. This ensures a seamless user experience, as the data is preserved, making it possible for users to continue their interactions without losing information.

In contrast, the other options serve different purposes: the page life cycle describes the stages a web page goes through when it is requested and rendered but does not specifically address data retention; CSS is primarily concerned with the styling and layout of web pages without any data management functionality; and HTML is used for structuring content on the web, but it does not inherently provide mechanisms for retaining information across page requests.