In Which of the Following Situations Would the Persons Be

In which of the following situations would the persons be partners?

A) A and B jointly own shares of the capital stock of a corporation, have a joint bank account, and have purchased real estate as tenants in common.They share the dividends on the stock, the interest on the bank account, and the net proceeds from the lease of the real estate.
B) A and B buy and sell real estate continuously over a five-year period, conducting a business of trading in real estate.They do not consider themselves partners.
C) A, B, and C each inherit an undivided one-third interest in a restaurant and decide to sell it because the market is such that they are assured a good price.
D) All of these.