8/12 and 9/12 shows them written both with a common denominator. When you find common denominators, you have to do the same to the numerator and denominator. The other answers have not done this. So we know it will not be the first choice because 3/4 cannot become a greater number by multiplying both the numerator and denominator by the same number. We know it won't be the second option because 3 isn't a factor of 8. It won't be the third option either because 3 is not a multiple of 2. So we are left with the last one.