Utilize the input text as a context reference, choose the right relationship between Discover Financial and Discover card from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

It accepts MasterCard Inc's MasterCard and Discover Financial Services Inc's Discover card in its physical stores.

Answer: product_or_material_produced