Exposure to products of combustion can be fatal due to which of the following?

Exposure to products of combustion can indeed be fatal due to various factors, which is why the answer encompasses all listed options.

Heat is a critical hazard; excessive temperatures can lead to severe burns and other heat-related injuries, ultimately resulting in fatal conditions if the exposure is prolonged or particularly intense.

Smoke presents a significant risk as it contains numerous toxic chemicals and particulates that can impair respiratory function. Inhalation of smoke can lead to asphyxiation or long-term respiratory disease, both of which can be lethal.

Gases produced during combustion, such as carbon monoxide, are highly toxic and can rapidly incapacitate individuals. Carbon monoxide is especially dangerous because it binds to hemoglobin in the blood more effectively than oxygen, preventing oxygen transport and leading to unconsciousness, brain damage, or death.

Taking all these factors into consideration, exposure to products of combustion can be fatally dangerous due to the combined effects of heat, smoke, and toxic gases, making "all of the above" the correct answer.