Agency is related to Central. Central is a synonym of Center. Center is a type of Class. Class is related to Scholar. 
Horn is part of Bull. Horn is related to Instrument. Instrument is related to Guitar. Pickup is part of Guitar. 
Agency <--RelatedTo--> Central <--Synonym--> Center --IsA--> Class <--RelatedTo--> Scholar 
Bull <--PartOf-- Horn <--RelatedTo--> Instrument <--RelatedTo--> Guitar <--PartOf-- Pickup 