Generate a topic word for the given sentence. A topic word is usually the name of a person, place, animal, concept or object the sentence is focusing on.

[EX Q]: christian lous lange (september 17, 1869 – december 11, 1938) was a norwegian historian, teacher, and political scientist.
[EX A]: christian lous lange

[EX Q]: the diplura are a biological order.
[EX A]: diplura

[EX Q]: celosia is a genus of plants in the family amaranthaceae.
[EX A]:
celosia