Which mixture is most suitable for producing a red-dominant violet?

Correct answer: More red and less blue

Violet is produced by mixing red and blue pigments. The visual character of the mixture depends on their relative proportions: increasing blue makes a bluer violet, while increasing red makes a red-dominant or reddish violet. Therefore, using more red and less blue gives the requested result. Option C would move the mixture toward a duller, warmer neutralised colour, and option D produces orange rather than violet. Option B is correct.