Here is a goal: To soften butter quickly.

Which way makes more sense to accomplish this goal?

Possible answers:
[a]. Pour frozen water into a glass to heat it up. Then, dump out the water and place it over the stick of butter. The butter will be softened within minutes without it completely melting..
[b]. Pour boiling water into a glass to heat it up. Then, dump out the water and place it over the stick of butter. The butter will be softened within minutes without it completely melting..
[b].