词典只告诉你inform可以搭配of和about这二个介词，但介词的意义有所不同。

这类似于：Tell me your name. Tell me about your name. 前者的回答只需给出你的名词即可。后者则要解释你的名字但含义，为什么父母给你起了这样一个名字。或者你为什么跟母亲姓而不是跟父亲姓等等。

介词of常可表示动宾关系。inform sb of sth. 类似于于tell sb sth。inform sb about sth 类似于 tell sb about sth.

新概念课文如下：

A pilot noticed a balloon which seemed to be making for a Royal Air Force Station nearly. He informed the station at once, but no one there was able to explain the mystery. The officer in the control tower was very angry when he heard the news, because balloons can be a great danger to aircraft. He said that someone might be spying on the station and the pilot was ordered to keep track of the strange object. The pilot managed to circle the balloon for some time. He could make out three men in a basket under it and one of them was holding a pair of binoculars. When the balloon was over the station, the pilot saw one of the men taking photographs. Soon afterwards, the balloon began to descend and it landed near an airfield. The police were called in, but they could not arrest anyone, for the basket contained two Members of Parliament and the Commanding Officer of the station! As the Commanding Officer explained later, one half of the station did not know the other half was doing!

如果这个题是说飞行员第一次发现气球后就通知基地，则应该用of.

如果这个题是说飞行员监视气球，随时通知基地气球的动向，则应该用about。

所以这个题的设计不够严谨。