Directions : In these questions , a part of the sentence is given in bold . Below are given alternatives to the bold part at (A) , (B) and (C) which may improve the sentence . Choose the correct alternative . In case no improvement is needed you answer is (D ) .

Q:

One of the factor for her failure is the lack of concentration in studies.

• 1
  one of the factors
• 2
  each of the factors
• 3
  one of a factor
• 4
  No improvement