I wanted to help those homeless children in the Big Earthquake,

_______ I donated my pocket money that I had saved for two months.[ ]

A. so

B. because

C. since

鼻外伤时治疗鼻粘膜撕裂所致的鼻出血最适宜的方法是（）

A.输血

B.烧灼法

C.鼻腔纱条填塞

D.血管结扎法

E.血管栓塞法