“找客戶實操過程”見面課中提到的谷歌搜索引擎優(yōu)化，是的以下哪個縮寫？（）

We wih to acknowledge receipt of your letter of March 15,（）reached us yesterday.

As we are heavily committed,we are sorry that we are not in a（）to accept new orders.

We are glad that in the past few years,（）joint efforts,have greatly promoted both business and friendship.

Your quotation happens to be exactly the same（）we have received from Australia.

We are glad to enter （） business relations with your corporation.

As to chemical products we are well connected（）the major producers in America.

We hereby register a claim with you（）the basis of here,we can obtain a number of orders for you.

Risks other（）All Risks and War Risk can be covered if the extra pr－ enium should be borne by the buyer.

We trust the mentioned shipment will reach you（）sound condition.