Maximum recombination percentage is

Answer: Option C

The maximum recombination percentage is 50.
The recombination frequency between two genes cannot be greater than 50% because a random assortment of genes generates 50% recombination (non-linked genes produce 1 : 1 parental to non-parental. Thus, the recombination frequency would be non-parental/total → $$\frac{1}{1+1}=50\%$$  ).