Final answer:
Collateral services providers offer support services to the advertising industry, with public relations firms and market research firms being examples of such providers. They help in promoting a favorable image and understanding consumer behavior, respectively.
Step-by-step explanation:
Collateral services providers are specialized agencies or firms that offer support services to the advertising and promotions industry. These services are often complementary to the core advertising efforts and help in the creation and promotion of a product or brand image.
Among the options provided:
- Public relation firms
- Sales promotion agencies
- Digital marketing agencies
- Full-service interactive agencies
- Market research firms
Both public relations firms and market research firms fall into the category of collateral services providers. Public relations firms manage the communication between an organization and its public to promote favorable relationships and portray a desired image. Market research firms gather, analyze, and interpret data about markets, competitors, and consumer behavior to inform business decisions. The other listed agencies focus more directly on creating and implementing advertising and marketing strategies.