Which is one of the listed fire causes?

• A. Natural
• B. Accidental
• C. Arson
• D. Unknown

Answer: (D)

A fire cause is categorized to identify how a fire started. In investigations, causes are grouped into natural, accidental, arson, or unknown. The unknown category is used when the investigators cannot determine a specific source after examination, due to insufficient evidence or inconclusive findings. This makes unknown a valid listed fire cause because it represents cases where a definite ignition source isn’t established, rather than ruling out all possibilities. The other options describe specific, identifiable sources (natural events like lightning; accidental ignition from equipment or human error; arson as deliberate ignition), but the question asks which is one of the listed causes, and unknown fits as a legitimate category when a cause isn’t determined.