arrived 是关键词,所以A和D错误,因为A是现在完成时,D是现在完成进行时.
by the time一般来说要用于完成时态,且过去完成式更多些,但是也有例外.
主要是看主句的动作是否在从句动作发生前就结束了.
比较：
By the time l got to the station,the train had already gone.我到车站时,火车已经开走了.
By the time I was ten,my father was working in a small factory.
到我十岁时,我父亲一直在一家小工厂上班.（不是说他已经上完班,或者不在那里上班了.）
By the time the war was over ,death and suffering were to be seen everywhere.
到战争结束时,死亡和灾难将随处可见.（死亡和灾难可能要持续到战争结束之后很久,而不是在战争结束之前.）
希望能帮到您.