盐酸酸洗、酸浸适用于（）井。
A.碳酸盐岩油层
B.砂岩油层
C.泥质砂岩油层
D.井筒及炮眼有结垢的井
参考答案：D
The president of the university arrived yesterday, _____ the start of his short visit to China.
A．marked
B．having marked
C．marking
D．to mark
矩阵制结构主要适用于____。
