Final answer:
The song that the owners of Two Bobs Tires wrote represents the tagline of their business identity.
Step-by-step explanation:
The song that the owners of Two Bobs Tires wrote, which ends with the phrase 'Tell 'em two Bobs sent you!', represents the tagline of their business identity. A tagline is a short and memorable phrase that is used to sum up a company's brand message and differentiate it from competitors. In this case, the tagline is used to reinforce the unique identity of Two Bobs Tires and encourage customers to mention their name when making a purchase.