I'm fairly sure that the answer is an ecosystom.
2 m - polyester fabric: 4, cotton fabric: 14
6 m - polyester fabric: 12, cotton fabric: 42
8 m - polyester fabric: 16, cotton fabric: 56
9 m - polyester fabric: 18, cotton fabric: 63
check:
2 m: 4/14=2/7
6 m: 12/42=2/7
8 m: 16/56=2/7
9 m: 18/63 = 2/7
It totals out to 4. I/3 plus 2/3 would equal 1 whole number, then add 1+2+1, you will get 4!
I think its b because of its relation to the base
