One Can Become a Shareholder

One can become a shareholder:

A) by buying newly-issued shares that are sold through a stockbroker but which have not been underwritten.
B) only by subscribing to shares that are being issued by an existing corporation.
C) by buying newly-issued shares that have been underwritten by an investment banker and also sold by him.
D) by subscribing to shares in a new corporation and having them accepted by the board of directors after incorporation.