1.She stopped to help the boy______.

1.因为although是从属连词,故只能接从句,A选项不是从句,而是非谓语doing结构,故不能选.B选项是although接的从句,只不过也是省略句,省略了主谓,补充完整是although(she was) in a hurry.注意：从属连词后面省略主谓,注意是一起省略,是英语中常见的.比如：if(it is) necessary.when(you are)eating.
2.这道题不管选哪个都是有问题的.因为,两个分句之间缺少连接词.下面是正确的：
Ever since I met her in 1976,we.
I met her in 1976.From then on we haven't met each other.
I met her in 1976.We haven't met each other from then on/ever since.