A browser's default action can be prevented by returning the _____ value from an event handler function.

In many recursive operations on lists,

A) the base case of the recursion corresponds to the empty list B) some operation that does not require recursion is performed on the head element C) a recursive call is made on the tail of the list D) All of the above

In order to use recursion on linked lists

A) it is necessary to modify the class that represents nodes, by adding a reference needed to support recursion B) the class that represents nodes must implement the Repeatable interface C) no changes to the node class are necessary D) A and B are both true