“Soda” vs. “Pop” Which is correct? [POLL]

What started as a polite gesture has turned into a heated debate in our office. While heading to the vending machine, I asked a coworker if she would like a pop. She promptly corrected me stating that it is called a soda.

30 minutes later... I'm still thirsty and we have gotten nowhere with this debate.

So we leave it to you. What do you call it?