Code example 7-1 1. var eventHandler = function(evt) { 2. if (!evt) { evt = window.event; } 3. if (evt.preventDefault) { 4. evt.preventDefault(); 5. } 6. else { 7. evt.returnValue = false; 8. } 9. };

(Refer to code example 7-1) This is cross-browser compatible code that cancels the default action for an event. What do lines 3 - 5 do?

They cancel the default action of the event for all modern browsers.

They cancel the default action of the event for older versions of IE.

They check to see if the page is DOM-compliant.