The Customs surveillance zone include the following places except ______.

A．any seaport, railway and high way station, airport, border pass or international postal matter exchange where there is a Customs establishment

B．any place where Customs control is conducted

C．any place without a Customs establishment but which has been approved by the state council as a point of entry and exit

D．any place along the border of the country

为了除去粗盐中的Ca²⁺,Mg²⁺,SO₄^2-及泥沙,得到纯净的NaCl,可将粗盐溶于水,然后在下列操作中选取必要的步骤和正确的操作顺序 ①过滤; ②加过量NaOH溶液; ③加过量盐酸; ④加过量NaCO₃溶液; ⑤加过量

BaCl₂溶液[ ]

A.④②⑤

B.②⑤④①③

C.④①②⑤③

D.①④②⑤③