Which of the Following Is an Example of Internal Marketing

Which of the following is an example of internal marketing conducted by a chain of dog kennels that boards and grooms pets?

A) A publicity article in the neighborhood newspaper describing the exclusive training received by the kennel's employees.
B) An e-mail to one of the employees praising him for finding and returning a customer's dog collar.
C) A newspaper advertisement showing a picture of happy dogs staying at the kennel.
D) A tour of the facilities available at the kennel targeted at elementary school children.