Civitas is a large urban city and until recently the municipal government provided a set number of licences $($one per car$)$ to operate taxi services in the city. Under this scheme, a small number of companies owned all of the licences and it was extremely difficult for people to hail a taxi during times of high demand. Recently, Uber, a ride sharing company, successfully entered the market and simply ignored the city's licencing scheme. Which of the following set of market structures most closely approximates the nature of the taxi industry, before and after, the entrance of Uber in Civitas?