*$_Air is to be heated by condensing steam. Two heat exchangers are available (i) a shell and tube heat exchanger and (ii) a finned tube heat exchanger. Tube side heat transfer area are equal in both the cases. The recommended arrangement is?

• A. Finned tube heat exchanger with air inside and steam outside
• B. Finned tube heat exchanger with air outside and steam inside
• C. Shell and tube heat exchanger with air inside tubes and steam on shell side
• D. Shell and tube heat exchanger with air on shell side and steam inside tubes