（ ） 銀行為其客戶開發擔保信用狀，因這類交易多無買賣或無對價行為，風險甚高，糾紛很多，尤其金額愈大，期間愈久者，銀行不可不小心處理，應在擔保信用狀上做下列何項敘述，方為妥當？
(A) This L/C is available for payment at our counter by beneficiary's draft drawn at sight on us
(B) This L/C is transferable at the beneficiary's country only
(C) This L/C may be negotiable with the advising bank only
(D) This L/C is valid until-in your country, and is automat1ically re-newable for one year upon each expiry date（s）。