应首先考虑

A．急性化脓性胆囊炎

B．胆囊穿孔

C．坏死性胰腺炎

D．急性化脓性梗阻性胆管炎

E．肝内胆管结石

In the foreign trade business, the payment is always made by L/
C．In this sentence, L/C is the abbreviation for ______.

A．bill of Lading
B．commercial Invoice
C．buying Contract
D．letter of Credit