91. 信用狀有關提單之敘述為「FULL SET OF CLEAN ON BOARD OCEANBILLS OF LADING MADE OUT TO ORDER OF SHIPPER MARKED“FREIGHT PREPAID”」，受益人押匯時必須提示何種提單？ (A)全套、清潔及記名式提單 (B)備運、清潔及指示式提單 (C)全套、運費預付及指示式提單 (D)清潔、運費到付及指示式提單。