58.This line has proved so popular that we regret to inform you that ______.　(A)it is no longer in production　(B)it has sold out　(C)it is out of stock　(D)it has been discontinued

57.We have to inform you that the model in question has already been discontinued. (譯成中文)　(A)您所詢問的模型已寄出，就此通知　(B)有疑問的模型已不再能繼續使用，就此通知　(C)該機種已停產，就此通知　(D)有問題的機種已經停產，就此通知。