One way to compare fractions is by making the denominator same and then comparing the numerator, the greater the numerator, the greater is the fraction.
Now to make the denominator same , we can take LCM of all the denominator involved i.e. LCM of 3,4,6,9,18 -> 36

so the answer to the question must lie between 2*12/3*12 =24/36 and 5*6/6*6=30/36 i.e. 24/36<X< 30/36.
Looking at the answer choices B,C,D will fall in the range.
a. 11/18 = 11*2/18*2 = 22/36 (outside the range)
b. 13/18 = 13*2/18*2 = 26/36 (inside the range)
c. 3/4 = 3*9/4*9 = 27/36 (inside the range)
d. 7/9 = 7*4/9*4 = 28/36 (inside the range)
e. 8/9 = 8*4/9*4 = 32/36 (outside the range)

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