Objective: How to Whistle

Which of the following solutions is more sound in terms of naive physics reasoning?

OPTIONS:
(1). You can use your thumb and middle finger, or the thumb and index finger. It doesn't matter which two fingers you use. Use the two fingers that feel most comfortable to you.
(2). You can use your big toe and pinkie toe, or the big toe and index finger. It doesn't matter which two toes you use. Use the two toes that feel most comfortable to you.
(1).