In below compare the bold part of each sentence with expressions A, B, C, D and E. choose the correct expression which is an improvement upon the bold part.They should have calmly thought of the advantages that would accrue to them.

• A. should have been calm in thinking about
• B. should be calmly thought of
• C. shall have to calmly thought of
• D. should have calmly think of
• E. No correction required

Answer: (E)