UPPSC PCS 2017 · Question 90 of 149
Science
The combustion of hydrogen produces water, which is not a pollutant. Other given alternatives emit more amount of carbon which is the biggest source of air pollution.
Source: edurev.in UPPSC Prelims 2017 GS Paper I with Answer Key and Solutions
Practice the full UPPSC PCS 2017 paper
Timed test with all 149 questions, just like the real exam.
Start test