Select the incorrect reason from the following:

Coal is not considered to be an ideal household fuel because _____________.

The incorrect reason is - its ignition temperature is low.

The ignition temperature of coal is high. This means it will take a lot of time for coal to burn. When coal burns it gives less energy and more ash as the product. Thus a lot of fuel is wasted. It produces smoke, sulphur dioxide, and unburnt carbon particles which can cause harm to the human body.  So coal cannot be considered to be an ideal household fuel.