Selling of the Option

Trading
1

What happen to Sell of Nifty Call option if Nifty price is below the CE strike price on last day ?

As it is sell , so is it compulsory to buy at closing day ?

Thanks

2

No need to buy you will get the full premium credited.

3

Thanks for reply.

What will happen if I have bought a option and profitable on last day; in that situation –
1 ) can i have to compulsory sell
or
2) can leave as it is ?

Regards,