Q. An element playing important role in nitrogen fixation is :

Q. An element playing important role in nitrogen fixation is :

(a) Copper

(b) Manganese

(c) Boron

(d) Molybdenum

Solution :

Correct option : D 
Molybdenum plays important role in nitrogen fixation as it is a key element of nitrogen-fixing enzymes i.e., nitrogenase, nitrite reductase and nitrate reductase. It is present in the conjugated form with iron in these enzymes. Thus, the correct answer is D.