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UPPSC PCS 2019 · Question 139 of 150

Which of the following is associated with biological nitrogen fixation?

Science & Tech

  1. ARed algae
  2. BBrown algae
  3. CGreen algae
  4. DBlue-green algaeCorrect

Answer: D. Blue-green algae

Explanation

Blue-green algae (cyanobacteria) fix atmospheric nitrogen.

Source: https://theexampillar.com/uppsc-pcs-acf-and-rfo-pre-exam-paper-2019-paper-1-in-english-answer-key/

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