Determine the topic of the question. Question: "what is a book index?" Topic:
Ans: Index (publishing)

Determine the topic of the question. Question: "who wrote what's my name rihanna?" Topic:
Ans: What's My Name? (Rihanna song)

Determine the topic of the question. Question: "what is ratchet from ratchet and clank?" Topic:
Ans: Ratchet & Clank

Determine the topic of the question. Question: "where is testosterone produced?" Topic:
Ans: Testosterone