Determine the topic of the question. Question: "what cars have smart key systems?" Topic:
Ans: Smart key

Determine the topic of the question. Question: "how does a solid state drive work?" Topic:
Ans: Solid-state drive

Determine the topic of the question. Question: "what is middle class in the us?" Topic:
Ans: American middle class

Determine the topic of the question. Question: "what is tmz stand for?" Topic:
Ans: TMZ (website)