Put the words in brackets into the present perfect continuous.

I _____ (has/ have) been studying in Salvador Dali art college (from/since) 2021.



a.
I has been studying in Salvador Dali art college since 2021.



b.
I have been studying in Salvador Dali art college since 2021.



c.
I has been studying in Salvador Dali art college from 2021.



d.
I have been studying in Salvador Dali art college from 2021.