UPSC Prelims GS - 2023

Question 30
DIFFICULTCorrect: +2Incorrect: -2

Consider the following:
1. Aerosols
2. Foam agents
3. Fire retardants
4. LubricantsIn the making of
how many of the above are hydrofluorocarbons used?

    a
    Only one
    b
    Only two
    c
    Only three
    d
    All four