Which process is correct for making a series of lighter versions of one colour?

Correct answer: Gradually increase the amount of white in each next sample

The governing concept is value variation through tints and shades. Gradually adding increasing amounts of white to the same base colour produces a tint scale, meaning progressively lighter versions; therefore option B is correct. Increasing black produces darker shades, while adding a complementary colour generally reduces saturation and may make the colour duller. Keeping the same ratio does not create a lighter series.