What aspect of fire investigation was highlighted by unusual flame patterns?

Unusual flame patterns can serve as significant indicators of arson in fire investigations. These patterns might include irregular burn marks, excessive charring in specific areas, or flames that defy the expected behavior based on the materials present. When an investigator observes such patterns, it raises questions about whether the fire was intentionally set. For instance, the presence of multiple points of ignition or burn patterns that suggest an accelerant was used supports the theory of arson. Hence, unusual flame patterns are closely examined to determine their correlation with potential malicious intent, making them a key aspect in identifying arson incidents.

While the other options also relate to fire investigation, they do not directly connect the specific aspect of unusual flame patterns to identifying an intentional act like arson. Electrical failures, flammable materials, and structural damage might all play a role in understanding a fire, but unusual flame patterns specifically point toward deliberate actions taken to ignite the fire.