My brother-in-law is a F1-student, Can I show him as a "Qualifying Relative" for my tax returns? Is he a resident-alien or non-resident alien?

Hi I provided 100% of expenses for my brothrer-in-law in year 2017 who is a F1-student pursuing his masters. He meets all other criteria for a "Qualifying Relative" except that I am not sure if he is resident-alien or a non-resident alien.