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Railways PYQCBT 1 2016

RRB NTPC · Question 17

Which of the following is a nitrogen-fixing bacteria? A. Salmonella B. Rhizobium C. E.coli D. Pseudomonas

  1. D

  2. A

  3. B

  4. C

Show answer & explanation

Answer: (C) B

Explanation

Rhizobium bacteria live in root nodules of leguminous plants (peas, beans) and convert atmospheric nitrogen into ammonia that the plant can use. Salmonella and E. coli are gut bacteria, and Pseudomonas is not a symbiotic nitrogen fixer.