单项选择题

After reading his daughter's letter,the old man was so disappointed that he tore it into pieces with trembling fingers.()

A.老人读完女儿的信后失望至极,竟用颤抖的手指把它撕得粉碎。
B.读完女儿的信后,老人很失望,然后用颤抖的手指把信撕得粉碎。
C.老人读完女儿的信后很生气,竟用颤抖的手指把信扔到地上。
D.读完女儿的信后,老人很伤心,所以用颤抖的手指把它撕碎了。