这是个虚拟语气的句子
参考：
1.条件句中虚拟语气的形式
从句中提出一种与客观现实不相符或根本不可能存在的条件,主句会产生的一种不可能获得的结果.条件句中的虚拟语气根据不同的时间有三种不同的形式.
时间
从句谓语形式
主句谓语形式
将来
动词过去式(be用were)
should + 动词原形
were to + 动词原形
would / should / might / could + 动词原形
现在
动词过去式(be 用 were)
would / should / might / could + 动词原形
过去
had +动词过去分词
would / should / might / could have + 动词过去分词
2.条件句中的虚拟语气的举例
(1) 将来时的条件句中的虚拟语气.如：
If he should go to Qing Hua University,he would make full use of his time.如果他要上清华大学的话,他就会充分利用他的时间了.
If he were to come here,he would tell us about it.如果他要来的话,他会通知我们一声.
(2) 现在时的条件句中的虚拟语气.如：
If he were free,he would help us.要是他有空的话,它会帮助我们的.
If he studied at this school,he would know you well.如果他在这所学校学习的话,它会对你很熟悉.
(3) 过去时的条件句中的虚拟语气.如：
If I had seen the film,I would have told you about it.我如果看过这场电影,我会把电影内容告诉你了.
If I had got there earlier,I would have met Mr.Li.如果我早点到那儿,我就会会到了李先生.
3.运用条件句中的虚拟语气时,须注意的几个问题
(1) 当从句的主语为第三人称单数时,谓语动词若是系动词be时,可用 was 代替 were.但在倒装虚拟结构及 if I were you,as it were 中,只能用 were.如：
Were I ten years younger,I would study abroad.要是我还年轻十岁的话,我会去国外学习.
If I were you,I would try my best to grasp the chance.要是我是你的话,我要尽力抓住这次机会.
建议你把最后一句话好好读读,你会明白答案为什么是 A 哟.
不明白的再问哟,请及时采纳,多谢!