Consider the following plants:

  1. Clovers
  2. Soybeans
  3. Alfalfa

Which of the above is/are useful in biological nitrogen fixation? 

Answer: [D] 1, 2 & 3

Biological nitrogen fixation (BNF) is the process whereby atmospheric nitrogen (N=N) is reduced to ammonia in the presence of nitrogenase.  Plants that contribute to nitrogen fixation include the legume family such as kudzu, clovers, soybeans, alfalfa, lupines, peanuts, etc.

This question is a part of GKToday's Integrated IAS General Studies Module