Are these competitive markets?

a. in a small town, there are two providers of broadband internet access: a cable company and the phone company. the internet access offered by both providers is of the same speed.

b. several stores in the mall sell hooded sweatshirts. each store's sweatshirts reflect the style of that particular store. additionally, some stores use higher-quality cotton than others, which is reflected in the apparel's prices.

c. scholastik inc. owns the u. s. copyright to a popular book series. it is the only company with the legal right to publish books in the series in the united states.

d. dozens of companies produce plain white socks. consumers regard plain white socks as identical and don't care who manufactures their socks.