____ her friend was badly hurt, she burst into tears.

A．Hearing

B．Having heard

C．To hear

D．Heard

根据语境，仿照画线句，将下面的句子补充完整。

　坚忍是达到成功的阶梯。春蚕忍受着茧的束缚，把纷飞的梦想留给明天；　　　　,        ；海蚌忍受着沙石的打磨，把晶莹的珍珠留给明天。