Choose the suitable Adjective Clause from the options given below:

I have invited my friends _________ parents are in India.

whose

The correct answer is Option (1) - whose

The suitable adjective clause is: whose

The complete sentence would be: I have invited my friends whose parents are in India.


Whose is used to show possession and is appropriate when referring to someone's parents.
Which, this, and when are not suitable for indicating possession in this context.