Item A, because the bilateral contract contains the future obligations of the buyer and the seller, both parties will face the risk of the other party's breach of contract, while the unilateral contract only exposes the buyer to this risk; In item C, if a forward contract is to be terminated midway, both parties must agree, and no unilateral will can terminate the contract, and its physical delivery ratio is very high; In item D, the futures contract has a hedging mechanism, the physical delivery ratio is very low, and the transaction price is limited by the minimum price change unit and daily fluctuation. Item B, the credit default swap contract is called a unilateral contract because only one party has the obligation in the future, which only allows the buyer to bear the default risk of the other party.