Oil Colour Painting

Correct answer: B. Oil paint does not dissolve in water

Explanation: The governing concept is the compatibility of a painting medium with its thinner. Oil paint is made with an oil-based binder, whereas plain water is polar and does not combine properly with that binder. Therefore, water cannot thin oil paint into a smooth, stable mixture, so option B is correct. Options A, C, and D do not describe the actual material property involved; an appropriate oil-compatible medium is used instead.

Correct answer: A. Colour may become muddy

Explanation: The governing concept is clean-tool control during colour mixing. A dirty brush carries remnants of earlier pigments into the next mixture, so unwanted colours combine and the new colour can become dull, greyish, or muddy. Thus, option A is correct. A dirty brush does not reliably increase brightness, thicken the paper, or make the drawing dry automatically. Washing and gently drying the brush between different colours helps preserve hue, brightness, and predictable mixing results.

Correct answer: A. They dry slowly and allow blending.

Explanation: Oil colours dry slowly, so an artist gets enough time to blend colours, soften edges, and make corrections. Option B is more suitable for fast-drying media such as watercolours or acrylics, not oil colours. Exam tip: Remember oil colours for their slow drying time and rich colour effects.