Try to end your story on a decision so someone else can resolve it somehow in the options.
The body for each option will remain blank so that others can fill them in.
Since you're the author, you can always add more options after publishing.
If you let others add new options, they can continue the story however they want.
If you want to end the story here, don't add any options and don't let others add new ones.
Allow others to add new options: