What kind of colour generally forms by mixing blue and orange?

Correct answer: Muted brown or grey

The governing concept is complementary colour mixing. Blue and orange occupy opposite positions on the colour wheel, so they are complementary colours. In pigment mixtures, their opposing colour qualities reduce saturation and generally produce a dull brown, grey, or other muted neutral. Therefore option B is correct. A bright green would require a different combination, while pure red or light yellow is not the normal result of mixing this complementary pair.