UPSC Prelims GS - 2017

Question 9
EASYCorrect: +2Incorrect: -2

Biological Oxygen Demand (BOD) is a standard criterion for

    a
    Measuring oxygen levels in blood
    b
    Computing oxygen levels in forest ecosystems
    c
    Pollution assay in aquaticecosystems
    d
    Assessing oxygen levels in high altitude regions