55 買賣契約如約定〝3,000 M/T plus or minus 10%, at seller’s option. January, Februaryand March shipment equally divided. Each shipment shall be regarded as a separateand independent contract.〞，賣方若一月份交貨 1,000 M/T，二月份交貨 900 M/T，則其三月份交貨數量的彈性區間為
(A) 990 M/T〜1,210 M/T
(B) 800 M/T〜1,400 M/T
(C) 900 M/T〜1,100 M/T
(D) 800 M/T〜1,000 M/T