In the Early Part of the Twentieth Century,it Was Incredibly

In the early part of the twentieth century,it was incredibly dangerous to be a child,with almost 200 children killed in New York City streets in 1911.In 2009,only 14 children were killed in motor vehicle accidents in New York City,despite the growing population.What does this mean sociologically?

A) Children became increasingly intelligent, learning how to avoid dangerous situations.
B) New immigrants are more protective of their children.
C) There is less social inequality among children.
D) American children lost their economic value and achieved a new emotional value.