What qualifies as a competent ignition source?

A competent ignition source is defined as one that possesses sufficient energy to ignite a fuel material. This means that the source must not only be present but also have the capability to raise the temperature of the fuel to its ignition point, effectively starting combustion.

Considering this, the other options do not meet the specific criteria for competency as an ignition source. Merely having a heat source present at a fire scene does not guarantee that it has the necessary energy to ignite any materials. Similarly, an ignition source that is easily extinguished does not imply that it is competent, as it may not sustain the ignition long enough for combustion to occur. Additionally, a source that is limited to igniting only organic materials does not encompass the wider range of potential fuels that could be present in a fire scene, thus failing to meet the broad applicability necessary for a competent ignition source.

By focusing on the energy requirement, option B accurately defines a competent ignition source in the context of fire investigation.