What is the best way to add google analytics tracking for specific elements on the page?

Question

All important elements on my page has ID attribute set. I want to track if visitors are really using (clicking) those elements and I'm not sure which one of those 3 ways is the best:

I - add onclick="track..." at the page generate time II - add onClick handler after ondomready for each element III - add only one onClick handler for whole body and then use event bubbling to determine what was clicked