Which statement about fire investigations is true?

• A. Every fire has a determinable cause.
• B. Some fires may have unknown causes.
• C. Investigations always identify the ignition source immediately.
• D. Fire investigations are not used in residential fires.

Answer: (B)

When assessing fire investigations, it’s important to understand that finding a cause isn’t always possible. Investigators look for the origin and ignition source by examining burn patterns, debris, and available evidence, but sometimes evidence is lost, damaged, or inconclusive, leaving the cause unknown. That’s why some fires have unknown causes as a legitimate outcome.

The other statements don’t fit: not every fire yields a determinable cause; investigators don’t always identify the ignition source immediately; and investigations are conducted for residential fires just as they are for other settings.