Did he think the word was offensive?

I found yesterday to be very interesting, We visited the Birmingham civil rights institute. One thing I noticed was that all of the statues in the exhibits had no color, but I could still distinguish the difference between black and white people. 

There was a little white girl in the museum with her father and she ask "why were black people like that", her father then quickly shushed her and told her not to say black. This moment had me in deep thought. Did he think the word is offensive? Is blackness a taboo? Overall I think that silencing the young curios mind is bad and might only increase ignorance. If he'd answered her question maybe the young girl would have learned something.

Marie Mokuba, Baltimore City College