Answer: b

A. After the investor successfully subscribes for the fund on T day, the investor can redeem the fund shares from T+2 day; C. Regular fixed subscription generally has a minimum contribution amount per period; D. Front-end fees refer to the subscription fees paid by investors when they purchase funds, and back-end fees refer to the subscription fees paid by investors when they redeem funds. Front-end charges are generally classified according to the amount of investment, while back-end charges are classified according to the holding time.