Should I click on a dashboard graph and what should happen?

I have been wondering about a simple behavior around a dashboard graph:

Should I click on the graph?

If so, what should be the most effective action to take:

a) Open a table with graph data b) Drill down to a another graph with more detailed information c) Open a zoom window to detail a specific time interval

What would be the common sense regarding graph interaction? Should have graph interaction at all?