---May! How is your plan? I heard you started it last Sunday.

---Oh! I          for it, but I haven’t decided where to start it.

A．have prepared

B．had prepared

C．have been preparing

D．was preparing

已知二次函数y=ax²+bx+c的图象与x轴交于点（-2，0），（x₁，0），且1＜x₁＜2，与y轴的正半轴交于点（0，2）的下方，下列结论：

①a＜b＜0；②2a+c>0；③4a+c＜0；④2a-b+1>0，

其中正确的结论的个数为[ ]

A.1个

B.2个

C.3个

D.4个