Hey Jatin:)

Thanks for reaching out!

If biotechnology at NIT Agartala is showing in the CSAB choice filling portal,it means you can select it but that doesn't always means seats are available. CSAB portal shows all branches including those with zero vacancies. However,since this branch is not listed in the PDF released by CSAB it likely means there are no vacant seats right now.

CSAB still allows you to fill such choices so that if a seat becomes available later due to someone withdrawing or reshuffling,you can still be considered for it.

Note: It's advisable to include such options but make sure to keep branches with confirmed availability higher in your list incase no vacancy opens up later.

Hope this clears your query!