Select the most appropriate option to substitute the underlined segment in the given sentence. If there is no need to substitute it, select No Improvement. 

Q:

It would be wise to accept the company's offer lest you should regret later.

• 1
  lest you shall not regret
• 2
  lest you should not regret
• 3
  lest you would regret
• 4
  No substitution