Why is selecting adjacent colours necessary while making tertiary colours?

Correct answer: An adjacent primary and secondary make a clear tertiary colour

In the traditional colour-wheel system, a tertiary colour is produced by mixing a primary colour with the adjacent secondary colour, such as red with orange to make red-orange. These neighbouring colours create a recognisable, controlled hue. Mixing distant or unrelated colours can produce a dull or muddy result. Thus option B gives the correct reason; the other statements are either false or irrelevant.