The answer is: Visit different banks and find out how often it compounds, and she should find out the interest rate of each account to see which will earn her the most money.
The compound time for interest is usually given either yearly, quarterly, or monthly (longer compound time usually has higher interest rate).
Naomi need to evaluate her own economic needs and determine the best possible option for her. For example, if she is not planning to use her saving within short period of time, she could opt for longer compound time and higher interest rate since it would be beneficial for her the most.