Every other kind of sport had people outside ; hikers , bikers , boaters , rollerbladers , you name it . So where did the rock climbers go ? Now that there are indoor climbing walls , has everybody who likes to climb moved indoors ?
According to the above context, choose the best option to answer the following question.
Question: Why do n't rock climbers climb outside anymore ?
Options:
- None of the above choices .
 - They want to get more fresh air .
 - There is nothing to climb outside .
 - Indoor rock climbing walls are more convenient .


Indoor rock climbing walls are more convenient .