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Which alternative is something that can have an impact on genetic material, cause cancer and also contribute to the formation of tropospheric ozone?

  • Incorrect: Carbon dioxide (CO2)
  • Correct: Hydrocarbons (HC)
  • Incorrect: Nitric oxide (NOx)
  • Incorrect: Carbon monoxide (CO)

Hydrocarbons (HC) in car exhausts causes cancer and can have a genetic impact. Along with nitric oxides, the hydrocarbon emissions contribute to the formation of tropospheric ozone.” (Driving Licence Book, 19th Edition, page 228)

Sometimes, you have to give the answer that is the “most correct”. The increased risk of cancer caused by nitric oxide is so small that the STR Driving Licence Book does not even mention it. On the other hand, the Driving Licence Book does say that hydrocarbons “cause cancer”, which makes that alternative the most correct.


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