Answer: (D) Marketing channel or channel of distribution
Explanation:
The marketing channel is one of the type of organization that perform various types of activities for purpose of transmission of the products and the services from the manufacturer to the customer or the end user.
It is also known as the distribution channel and it include the various types of business strategies for promoting the product.
According to the given question, the Kayak is one of the type of organization that publicly allow their database for the purpose of searching the best deals for the hotels or airline.
Therefore, The kayak is one of the part of marketing channel or the channel of distribution.