What role does a web server play in relation to web browsers?

The correct role of a web server in relation to web browsers is to send requested web pages to users' browsers. When a user types a web address into a browser or clicks on a link, the browser sends a request to the web server that hosts the website. The web server processes this request and sends back the appropriate webpage, which the browser then renders for the user to view. This communication between the server and the browser is fundamental to how the web operates; without a web server, browsers would not be able to access and display websites.

In terms of the other options, enhancing browser speed pertains more to the efficiency of the browser itself or techniques like caching, and is not a direct function of the web server. The blocking of unwanted browser extensions relates to the security features of the browser, not the functionalities of a web server. Storing users' browser history is a function handled by the browser itself, as it tracks the pages visited by the user for future reference. Therefore, the primary interaction of a web server is to provide the necessary resources that browsers request, which makes the correct answer clear.