excuse me,do you know miss black's telephone number?sorry,i don't know.she ( )it since yesterday.a.has changedb.have changed为什么?she 不是应该选a的吗

excuse me,do you know miss black's telephone number?sorry,i don't know.she ( )it since yesterday.a.has changedb.have changed为什么?she 不是应该选a的吗
excuse me,do you know miss black's telephone number?sorry,i don't know.
she ( )it since yesterday.
a.has changed
b.have changed
为什么?she 不是应该选a的吗

excuse me,do you know miss black's telephone number?sorry,i don't know.she ( )it since yesterday.a.has changedb.have changed为什么?she 不是应该选a的吗
B 无论如何是不对的,请放心.
she 后面只能接 has 或 had （过去式）