如图是点电荷电场中的一条电场线，下列说法正确的是（　　）

A．A点电势一定大于0

B．B点的电势一定比C高

C．B点的场强一定比C强

D．该电场线一定是正点电荷形成的电场中的一条电场线

---The vase cost me almost 100 yuan.

---Well, it was crazy of you to spend so much money _____you could buy a much         cheaper one.

A．while

B．if

C．because

D．when