Watercolour

The governing concept is transparency: a thin paint film should allow some of the paper or lower layer to remain visible. Diluting the colour with a suitable amount of water and applying it with a light stroke produces that effect, so option A is correct. Thick paint and heavy pressure create stronger opaque coverage; dry paint with a metal tool is unrelated, and opaque white hides rather than reveals the underlying layer.

In the wet-on-wet method, moisture already present on the surface allows fresh paint to move beyond the immediate brush path. The colours therefore spread into one another and form soft, diffused edges. Option D is correct. A sharp edge is more typical of controlled wet-on-dry work, while wet paint does not harden the paper or prevent spreading.

The governing concept is gravity acting on a fluid wash. When the paper is tilted or the wash contains too much water, excess pigment-bearing liquid moves downward and gathers along the lower edge, producing a darker bead or tide mark. Therefore A is correct. Brush size, paper colour, and a dry palette do not explain this accumulation; the practical correction is to remove excess moisture with a clean, slightly damp brush.

The governing concept is moisture control during lifting in watercolour. A lifting brush should be clean and only slightly damp so it can absorb excess pigment without releasing much water. If it is too wet, it adds water to the still-active wash, spreading pigment outward and possibly creating a new bloom or cauliflower mark. Thus B is correct; the other choices contradict how water and transparent pigment behave.

The governing concept is tool suitability: the brush must provide enough stiffness and control for the resistance of the medium. Very soft watercolour bristles are designed to hold and release fluid paint gently, so they may bend or collapse when asked to move a thick mixture and may not push it effectively. Therefore B is correct. Drying, metallic surfaces, and bristle breakage do not logically follow from paint thickness alone.

The governing watercolour principle is water control. A damp brush should contain only enough moisture to soften the boundary; excess water forms a small pool, reactivates the dry pigment, and carries it beyond the intended edge. Thus option B identifies the main error. Brush size, colour darkness, and paper whiteness may affect appearance, but none directly causes this outward bloom as strongly as excess water.

The governing concept is glazing: a transparent film of colour is placed over a dry underlying layer. Because the upper layer allows light and some visual information from below to remain visible, the combined colour gains depth and often a richer optical effect. Option D is correct. The first layer is not erased, and transparency does not automatically make the result white; roughness is not the defining effect.

The governing concept is proper brush maintenance: acrylic is water-based when wet but forms a stubborn film when dry. If paint remains near the ferrule, it binds the bristles together, making them stiff and uneven. With repeated use, the brush loses its original shape, spreads, and becomes less flexible. Therefore, option A is correct; the other choices describe effects unrelated to dried paint in the bristles.

The governing concept is paint transparency: a dilute watercolour wash lets the paper or earlier layer show through. Adding a controlled amount of water and applying a thin, even layer lowers pigment concentration without making the wash uncontrolled, so option A is correct. Clay and a thick layer make the colour opaque, while a completely dry brush does not create a transparent wash.

The governing concept of a transparent wash is dilution. Adding a suitable amount of clean water lowers the concentration of pigment, allowing more of the paper to show through. Thus, option A is correct. Adding black usually changes the value and may make the mixture dull; brush pressure does not create transparency, and keeping paint dry makes it thicker rather than more transparent. Excess water should still be avoided because it can cause runs.

The governing concept is controlled layering in a transparent wash. The first layer should dry before another layer is applied, so its pigment remains settled and the new colour does not disturb or muddy it. Therefore, option C is correct. Rubbing can damage the paper, extra water can reactivate and spread the first layer, and folding the paper is unrelated. The required drying time depends on the amount of water, paper, paint, and surrounding conditions.

The governing concept is controlled liquid paint flow in a wash. A slight, steady tilt uses gravity to guide the wet paint in one direction, helping the artist maintain a moving bead and distribute colour more evenly. It does not instantly dry the paint, clean the brush, or change the paper itself. Therefore option A is correct, although excessive tilt can cause pooling.

The governing concept is colour lifting in watercolour. While the paint remains wet, a clean, damp brush can absorb some excess pigment from the dark area; the brush should be blotted first so it does not simply spread the colour. This lightens the tone gradually. Applying black makes it darker, scratching damages the paper fibres, and folding cannot correct the paint. Therefore, option B is correct.

The governing concept is moisture control in wet-on-wet watercolour. A puddled or excessively wet surface lets pigment travel rapidly beyond the intended mark, so the first correction is to remove or reduce excess surface water while keeping the paper suitably damp. Option A is correct. Adding water, wetting the paper further, or rubbing forcefully increases disturbance and makes the spread less controllable.

The governing concept is the difference between wet and dry colour appearance in watercolour. Watercolour washes often look somewhat darker while wet and lighter after water evaporates, so a practice swatch should be allowed to dry before judging its final value. Adding black to every colour distorts hue, permanently wet paper is impractical, and excessive thickness can damage the wash or paper.

The governing concept is the paint-to-water ratio. Adding more water generally lowers pigment concentration, increases transparency, and allows the mixture to flow more freely; using less water produces a denser, stronger, and usually less transparent mark. Since the colour pigment is otherwise the same, these properties can be compared meaningfully. Option B is correct, while the other options are unrelated to water content.

The governing concept of a transparent wash is controlled dilution and light application. The pigment must be diluted enough to leave the paper or underlying drawing visible, but not so much that the wash becomes weak and uncontrolled. Option A is correct because it balances colour and transparency. Thick paint, heavy pressure, or an opaque black layer covers the lines rather than preserving them.