The liquid which is applied upon the surface covered with pastel colour for stability is :

Question

Accepted Answer

The correct answer to the question is Option 3: Fixative.

1. **Explanation for Option 3 (Fixative):**
   A fixative is a liquid that is sprayed or applied onto artwork, particularly those created with pastel, charcoal, or pencil, to stabilize the medium on the surface. Pastel colors are known for their vibrant hues but are also quite delicate and prone to smudging or fading over time. Applying a fixative helps to bind the pastel particles to the paper, reducing the risk of smudging and preserving the artwork's appearance. Fixatives come in various forms, such as spray cans or bottles, and are specifically designed for use with dry media like pastels, making them the ideal choice for ensuring the stability and longevity of pastel artworks.

2. **Explanation for why the other options are incorrect:**

- **Option 1 (Turpentine):**
     Turpentine is a solvent commonly used in oil painting to thin paints and clean brushes. It is not used to stabilize pastel colors on a surface. Applying turpentine to pastel artwork would likely dissolve or damage the pastel rather than preserve it.

- **Option 2 (Coaltar):**
     Coal tar is a thick, black liquid derived from coal and is primarily used in industrial applications, such as roofing and paving. It has no relevance to art preservation or the stabilization of pastel colors. Using coal tar on artwork would be inappropriate and damaging.

- **Option 4 (Impasto):**
     Impasto refers to a technique in painting where paint is laid on the canvas very thickly, creating texture and dimension. It is not a liquid or substance used to stabilize pastel colors. Impasto is a method used in oil or acrylic painting, not applicable to pastel artworks.

In conclusion, the correct option is Fixative, as it is specifically designed to stabilize and protect pastel artworks, ensuring their longevity and preventing smudging. The other options do not serve this purpose and are not suitable for use with pastel colors.