Answer: ACD

In the pilot development stage, the development of my country's fund industry mainly showed the following characteristics: ① The standardized operation of funds has been greatly improved; ② On the basis of the successful pilot of closed-end funds, open-end funds were successfully launched, making my country's fund operation level achieve a historic leap; ③ The old funds were comprehensively regulated and cleaned up, and the vast majority of old funds were replaced through asset replacement, mergers, etc. were transformed into new securities investment funds; ④ The regulatory authorities issued a series of policies and measures to encourage the development of the fund industry, which played an important role in promoting the development of the fund industry; ⑤ The development of open-end funds opened up new opportunities for the innovation of fund products. of heaven and earth. Item B is a characteristic of my country’s fund industry in its rapid development stage.