What is the stock's opening price given the information below about orders that arrived overnight? Please show your work. Buy orders: 200 shares at the market price; 400 shares at $15.90; 300 shares at $15.89; 400 shares at $15.88; 300 shares at $15.87; 250 shares at $15.86; Sell orders: 350 shares at the market price; 500 shares at $15.85; 700 shares at $15.86; no orders at $15.87; 150 shares at $15.88; 800 shares at $15.89; 100 shares at $15.90.

A. $15.87

B. $15.88

C. $15.85

D. $15.89

E. $15.86