Need help on Web Application Exercise

Need help on Web Application Exercise for SyntaxEditor Code Snippet on Resource.ResourceTypeId in the ToDoDetail under Save action on Module 7

If(Index(UploadResource.Type, "image") <> -1,
Entities.ResourceType.Image,
If(Index(UploadResource.Type, "audio") <> -1,
Entities.ResourceType.Audio,
Entities.ResourceType.Other))

and what is the problem exactly?