The H.C.F. of a/b ,c/d ,e/f is equal to = ?

Answer: Option B

$$\begin{array}{rl}& \text{HCF of fractions}\\ & \text{ = }\frac{\text{HCF of Numerators}}{\text{LCM of Denominators}}\\ & \text{HCF of }\frac{a}{b}\text{,}\frac{c}{d}\text{,}\frac{e}{f}\\ & =\frac{\text{HCF of }a,c,e}{\text{LCM of }b,d,f}\end{array}$$