Answer: A

The theoretical price calculation formula of stock index futures: F (t, T) = S (t) + S (t) · (r-d) · (T-t) / 365, where t is the time variable of each item to be calculated; T represents the delivery time; T-t is the length of time from time t to delivery, usually calculated in days; S(t) is the spot index at time t ; F (t, T) represents the theoretical price of the futures contract delivered at time T at time t (expressed as an index); r is the annual interest rate; d is the annual index dividend rate. It can be concluded that item A does not affect the Shanghai and Shenzhen 300 stock index Theoretical futures prices.