An investor enters a day order to buy 200 shares of GGZ at 63. Three hours later, with GGZ trading above that price, he calls his registered representative wanting to change the order to a good-till-canceled order. The registered representative should:
I. immediately cancel the existing order.
II. leave the existing order on the order book.
III. immediately enter a new limit order to buy 200 shares of GGZ at 63 GTC.
IV. enter a new limit order to buy 200 shares of GGZ at 63 GTC before the next day's opening if the day order was unexecuted.
A) II and IV.
B) I and III.
C) I and IV.
D) II and III.
Answer: C) I and IV.