input question: Determine the topic of the question-answer pair. Question: "what are add ons?"; Answer: "Peripheral , an optional computer hardware component that significantly supplements or enhances the functionality of the original unit"? Topic:???
output answer: Add-on

Determine the topic of the question-answer pair. Question: "what are some chinese inventions?"; Answer: "China has been the source of many inventions , including the Four Great Inventions : papermaking , the compass , gunpowder , and printing (both woodblock and movable type )."? Topic:
----
Answer: List of Chinese inventions

Q: Determine the topic of the question-answer pair. Question: "who wrote white christmas?"; Answer: ""White Christmas" is an Irving Berlin song reminiscing about an old-fashioned Christmas setting ."? Topic:
A: White Christmas (song)

Question: Determine the topic of the question-answer pair. Question: "what are rocker arms??"; Answer: "Generally referred to within the context of the internal combustion engine of automotive, marine, motorcycle and reciprocating aviation engines, the rocker arm is an oscillating lever that conveys radial movement from the cam lobe into linear movement at the poppet valve to open it."? Topic:
Answer: Rocker arm

[Q]: Determine the topic of the question-answer pair. Question: "who makes blackberry?"; Answer: "The BlackBerry is a line of wireless handheld devices and services designed and marketed by Research In Motion Limited (RIM) operating as BlackBerry ."? Topic:
****
[A]: BlackBerry

Problem: Given the question: Determine the topic of the question-answer pair. Question: "what is in the preamble of the constitution?"; Answer: "The Preamble to the United States Constitution is a brief introductory statement of the Constitution's fundamental purposes and guiding principles."? Topic:
++++++++++++++++++++++++++++++++
The answer is:
Preamble to the United States Constitution