The Depository Bank for Futures Margin (hereinafter referred to as the Depository Bank) is a futures service institution, which is designated by the Exchange to assist the Exchange in the settlement of futures transactions. The ownership of the transaction shall supervise the futures settlement business of the depository bank. The establishment of futures margin depository bank is a necessary link for the closed operation of domestic futures market margin, and it is also an important institution to ensure the safety of investors' funds. Therefore, items A, B and D are correct. The futures settlement institution is responsible for the unified settlement, margin management and settlement of futures transactions of the exchange. Therefore, item C is wrong.