What is Distinguish between differentiated marketing and concentrated?

Undifferentiated Marketing: Sending the same promotional message to everyone (Promoting the city as a historic destination by placing ads in widely read newspapers)

Differentiated Marketing:Designing more than one promotional message, with each communicating different benefits (ex:Also targeting families by communicating a promotional message about the importance of children learning history)

Concentrated Marketing:Designing a promotional message that communicates the benefits desired by a single specific segment (ex: Promoting the city as historic by targeting elderly members of historical societies by placing ads in their newsletters)