Hi Subhadra,

Mop up round in West Bengal is a MANUAL ROUND. There will be no choice filling as it is not online. 

For participating in the mop up round, if you have already registered and paid the fee, then you need to go the college where mop up round is being conducted. The location is available on wbmcc.nic.in Over there you will be called rank wise and be asked if you want a seat among the leftover seats. If you say yes then you are allotted that college. If you say no then, if you got a seat in previous round then you will retain that seat. Or if you didnt get any seat in previous rounds you have to wait for the college round.