What is the relationship between 'TaskRabbit' and 'company' in the context of the input sentence.
Options: creator, original broadcaster, legal form, platform

The sector that encompasses Etsy ETSY, -2.79% HomeAway AWAY, +0.19% Uber and on-demand labor company TaskRabbit is called the sharing economy, based on the idea that these companies share human and physical resources in some way.
legal form