In Bangkok severe flooding, many major roads ________ north, towards the areas worst affected

by the flooding, were largely impassable. [      ]

A. to lead          

B. leading          

C. led            

D. to be led

关于SELECT语句哪个描述是对的（）

A.关键字必须大写

B.关键字可以缩写

C.SELECT语句必须在同一行写完

D.SELECT语句中可以进行算术运算