"The Colt revolver was:
a. The single most important development in firearms technology.
b. The single most important development in personal defense technology, at least for a small person's ability to defend herself against a group of larger assailants."

Agree or disagree with item a or item b, or both. If you disagree, please cite specific examples of more important development(s), and why you believe they are more important.

Impressively erudite answers in the comments! For further refinement:

For a., only consider firearms, not ammunition. This eliminates the (persuasive) argument in favor of the breech-loading metallic cartridge. It leaves an argument in favor of the machine gun--although one could counter-argue that the Gatling Gun was just a very sophisticated extrapolation of the revolver. To which one could sur-reply that the Gatling didn't change things all that much, in practice, but the Maxim Gun did, and the Maxim was in no way derivative of the revolver.

On b., only consider weapons, and not other technologies (such as telephones).