The correct answer is C. Carbon monoxide.
Incomplete combustion of a fuel is a chemical reaction that occurs when a fuel is not burned completely. This can happen for a number of reasons, such as a lack of oxygen, a too-rich fuel mixture, or a faulty engine. When a fuel is not burned completely, it produces carbon monoxide, which is a poisonous gas.
Carbon monoxide is a colorless, odorless, and tasteless gas that is very dangerous to humans. It is absorbed into the bloodstream through the lungs and can quickly lead to death. Symptoms of carbon monoxide poisoning include headache, dizziness, nausea, vomiting, confusion, and loss of consciousness. If you think you or someone you know has been exposed to carbon monoxide, it is important to seek medical attention immediately.
There are a number of ways to prevent carbon monoxide poisoning. One way is to make sure that all fuel-burning appliances are properly installed and maintained. Another way is to install a carbon monoxide detector in your home. Carbon monoxide detectors are relatively inexpensive and can save lives.
If you have any questions about carbon monoxide poisoning, please talk to your doctor or a poison control center.