Time for a new logo...

My company is rebranding and these are four concepts that I've been working on. The idea involves the boiling point of water and it's for a creative marketing agency.

A&B: The idea of boiling point in water.
C&D: The idea of an oven knob. Obviously the second is abstract and shows the rotation.

Any thoughts or ideas? I'd appreciate it.

Which one is your favorite?