ask my dearest teachers

I have no answers to the questions that I have looked up in the dictionary but cannot get, so I need your help , teachers. Thank you very much.
which expression doesn't match with each complete sentence and how to correct it .
1.We have to explain to you that_____.
A.we have been heavily burdened with the cost on opening an L/C
B. it has tied up a great deal of our fund to open an L/C
C. establishment of an L/C has involved us in a lot of expenses
2. We know that___, but we believe your accommodation in this term is quite necessary for promotion of our business.
A.your customary procedure of payment is to do business on L/C
B.your usual practice of payment is to purchase goods by L/C
c.yourrule of payment is to deal withe your customers on the L/C basis
3. As to terms of payment, we agree to _____ the value of your purchase.
A draw your attention to D/A at 60 days sight for
B. draw a draft on your at 60 days D/A for
C.drow on you at 60 days D/A against
D. draw D/A at 60 days sight against
4. We propose that we____.
A. remit you the whole amount of the goods by T/T
B. make remittance for the whole amount of the goods by telegraph
C. make payment for the whole amount of the goods by T/T
D. transfer the whole anount of the goods to us by telegrph

[Mister Micawber]

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