The correct option is C 39
Equivalent fractions are the fractions that have different numerator and denominator but are equal to the same value.
1×22×2=24, 1×32×3 = 36, 1×42×4=48
Options a, b and d can be obtained by multiplying the numerator and denominator of 12 with 2, 3 and 4 respectively but not option c. ∴, it is not an equivalent fraction.