Finish the following sentence with the best choice: How do I keep the contents of a cooler cool without using ice?

Choices:
- Put plastic bags filled with frozen pieces of fruit in the cooler, which also double as extra food when it thaws enough.
- Put plastic bags filled with frozen balls of glass in the cooler, which also double as extra food when it thaws enough.

Answer:
Put plastic bags filled with frozen pieces of fruit in the cooler, which also double as extra food when it thaws enough.