Prime number beetween 90 and 150

Hi all i wanted to do this exercise that professor give to our class but i dont know how to do it: Write a method, called first, that returns the most 'small prime number between 90 and 150.

Well that could be quite easy...if i could use cicles like FOR or similar, but i can't. I can just use IF, Array, Method and other really basic thing, no libraries.

The only 2 solution that i found is to write around 60 IF or just to write

int prime(){
    return 97;
   }

Help me to do it or i have to deliver it in this last way :'D