Three years ago, Growth Corporation issued 6,000 shares of $100 par, convertible, preferred stock for $105 per share. Each share of preferred can be converted into 4 shares of $1 par common stock. Half of the preferred shares were converted in the current year when the common stock was trading for $40 per share. The journal entry to record the conversion will include: Select one: O a. credit additional paid in capital on common stock $0. O b. credit additional paid in capital on preferred stock $15,000. O c. credit additional paid in capital on common stock $303,000. d. credit additional paid in capital on common stock $468,000