If brown made by mixing red and green appears too red, what should be increased to balance it?

Correct answer: Green

The governing concept is adjusting pigment proportions during colour mixing. If a red-and-green brown mixture looks too red, the red component is excessive relative to the green component. Adding a small amount of green moves the ratio toward balance and reduces the visible red bias, so option B is correct. Yellow may change the hue, white lightens it, and black darkens it rather than directly correcting the red-green proportion.