Highest uniformity is present in

Answer: Option C

The highest uniformity is present in a Single cross.
The single cross is a first-generation hybrid between two selected and usually inbred lines. The highest uniformity is present in a single cross because a single cross involves a cross hybrid of the first generation between two inbred lines.
Single cross hybrids are based on two parental inbred lines whereas three-way crosses first require the production of a single cross hybrid followed by its use as a female parent crossed to a male inbred line.