Disc is related to Contact. Contact is a type of Lens. Lens is a type of Organ. 
Sweet is related to Drop. Drop is related to Individual. Individual is a type of Organism. 
Disc <--RelatedTo--> Contact --IsA--> Lens --IsA--> Organ 
Sweet <--RelatedTo--> Drop <--RelatedTo--> Individual --IsA--> Organism 