Problem: Determine the topic of the passage. "Cartridge-operated extinguishers contain the expellant gas in a separate cartridge that is punctured prior to discharge, exposing the propellant to the extinguishing agent." Topic:

A: Fire extinguisher
Problem: Given the question: Determine the topic of the passage. "Plug-in (computing) , a piece of software which enhances another software application and usually cannot be run independently" Topic:
++++++++++++++++++++++++++++++++
The answer is:
Add-on
input question: Determine the topic of the passage. "Weather is driven by air pressure (temperature and moisture) differences between one place and another." Topic:???
output answer: Weather
Determine the topic of the passage. "They believe that the destruction of the present world system at Armageddon is imminent, and that the establishment of God's kingdom on earth is the only solution for all problems faced by mankind." Topic:
----
Answer: Jehovah's Witnesses
Q: Determine the topic of the passage. "The Four Thirds system is a standard created by Olympus and Kodak for digital single-lens reflex camera (DSLR) design and development.<ref name='DPReview.com 2001-02-13'>" Topic:
A: Four Thirds system
[Q]: Determine the topic of the passage. "Chaucer is a crucial figure in developing the legitimacy of the vernacular , Middle English , at a time when the dominant literary languages in England were French and Latin." Topic:
****
[A]:
Geoffrey Chaucer