Fact 1: Athermal insulator slows the transfer of heat.

Fact 2: Ice is a good thermal insulator.

Given the two facts above, answer the question "What is ice good at?" with the following options: 
- Physical weathering
 - Conducting electricity
 - heat production
 - water conservation
 - Slowing the transfer of ions
 - lowered energy cost
 - Slowing the transfer of heat
 - Heating up water


 

       Slowing the transfer of heat  