What statements about pastels is true?

Pastels are a type of art medium made from pure powdered pigment combined with a binder, resulting in a soft, chalky texture. They are known for their vibrant colors and can produce a wide range of effects, from delicate washes to bold strokes. Additionally, pastels can be used on various surfaces, including paper, canvas, and wood, and they require fixatives to prevent smudging and preserve the artwork.