2-Vincent Rowold

This is obvious design because each of these icons tells your exactly what you need to do and what happens when you do do when it happens. The affordance is high with the unlock button because it has an arrow to the right, looks like a button, and has a space that the button fits right into as you slide. The text tells you what to do and what it will do and the text also highlights in a wave motion from left to right telling you the direction to slide.