What does a URL router do for an MVC framework?

What does a URL router do for an MVC framework?

Converts the URL string into an entity, action, and parameters; perhaps via the $$explode$$ function that will convert a string to an array

The URL router is a function of the web server, not the actual PHP application, it is handled automatically

In a load balanced web server farm, it determines which specific web server will handle the request

It handles the configured connection to the database and sets a global $db object that is mapped to the corresponding database engine