You purchased 1,000 shares of XYZ stock on a margin of $80 per share with an initial margin of 40%. XYZ stock price suddenly drops to $50 and you receive a margin call. You want to partially liquidate your position and repay the loan with the proceeds in order to meet the maintenance margin requirement of 30%. You need to sell at least _________ (rounded up to the nearest whole number).

a) 867 shares

b) 869 shares

c) 863 shares

d) 865 shares