The Reserve Bank of India keeps on changing various ratios/rates frequently. Why is this done? I. To keep inflation under control. II. To ensure that Indian rupee does not lose its market value. III. To ensure that banks do not earn huge profits at the cost of public money. Select the correct answer using the codes given below:

• A.  Only I                         
• B.  Only II
• C.  Only III                       
• D.  All of these
• E.  None of these