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

प्र:

Sincere workers do not rest till they have reached perfection in their work. 

• 1
  they have achieved
• 2
  they having reached
• 3
  they had achieved
• 4
  No improvement