Read the following context and choose the best option to answer the question.
Context: I hope we 'll sit down and talk as easily as we do today . As corny as it might sound , the old saying is so very true . Make new friends , keep the old . One is silver , the other is gold .
Question: Why are friendships equated to silver and gold ?
Options: 
- They tend to cost a lot to maintain .
 - None of the above choices .
 - They are a material possession .
 - They are expendable .


None of the above choices .