I have a valid visitor (B1/B2) visa and am traveling to the U.S. for short-term business or tourism under the VWP?
No, you will travel on your visitor visa.
I do not have a visitor visa and am traveling under the VWP for short-term business or tourism?
Yes.
I do not have a visitor visa but I have another type of visa, for example, a student visa (F1), but am traveling under the VWP for short-term business or tourism?
Yes.