I didn't answer the phone( )I didn't hear it ringA if B unless C although D because

问题描述:

I didn't answer the phone( )I didn't hear it ring
A if B unless C although D because

D 因为‘ 我没接电话因为我没听到铃声响’

D咯 因果关系

选择D.
A 如果、B 除非、C尽管、D 因为
句子为过去式,所以排除A;B、C选项意思不通