二人对话：
Mike:Hi, look where you are going ! John: Oh,I'm terribly sorry.
A.I wasn't noticing.
B.I didn't notice.
我发现这道题网上有人选A，有人选B。
大家学校有些老师选A，有些老师说B正确，有些老师说2个都正确。
请教专家老师，到底是什么正确的额？假如2个都正确，2个含义的理解差别到底在哪儿？
应该选A.问题的重点在于wasn't noticing 有没留心，或因精神没办法集中而没注意到的意思，这是英语里容易见到的使用方法。B则只是没注意到，可能是多种缘由，可能不是没留心。所以，选A 最符合句子语境和英语惯用。请领会几个外媒例句：
1. I was afraid no one would laugh, and I wanted to pretend I wasn't noticing the audience. （假装没注意到观众）
2. I got some water in my boot. It got so cold that I wasn't noticing the pain anymore. It just became totally numb.靴子太凉了，以至于感觉不到疼痛了，脚都麻木了。
3. I was bummed I wasn’t noticing any big changes after 3 months and then this happened.
我非常难过，我居然没注意到三个月后的大变化，然后这所有就发生了。
