Bob's Barbecue Has Issued Preferred Stock That Is Callable

Bob's Barbecue has issued preferred stock that is callable.Which of the following is possible with this stock?

A) The investors can make Bob buy the stock back if it falls to a given price.
B) The investors can choose to receive interest payments instead of dividends.
C) The investors can exchange the preferred stock for common stock.
D) Bob can make the investors trade their preferred stock for common stock.
E) Bob can make the investors sell the stock back to the company.