When children hear a new word in a familiar context, they can simply add the word to the general category without fully understanding the word. This is called "."

This is called fast-mapping.

Explanation:

In cognitive psychology, fast-mapping refers to children's ability to learn words and concepts with minimal exposure to them. Children as young as two years old are able to use fast-mapping, associating new words quickly to the ones they have previously learned. Studies have shown, however, fast-mapping is unsuccessful when the child is exposed to the unknown word only once.

even though you have attached neither the chart nor the generalizations, i have located them online. the right answer is d, since they are asking you about a generalization. you can only infer from the chart that between 2008 and 2009 the number of employed workers decreased significantly (from over 115 millions to 107 millions approximately), which signals some type of economic crisis.