What are two reasons an artist uses chiaroscuro or shading in an artwork?

1. Contrast and realism

2. Three dimensionality

Explanation:

    Chiaroscuro is an oil painting technique developed during the Renaissance that uses strong tonal contrasts between the three-dimensional forms of light and dark for the model, often for dramatic effects. The underlying principle is that the solidity of the form is best achieved by the light falling against it. Artists known for the development of the technique include Leonardo da Vinci, Caravaggio and Rembrandt. It is a key element of black and white and low photography.

    The claroscuro, in a two-dimensional image, such as a wall, a panel, a screen, a paper photographic print, gives the illusion of relief, volumes mimicking the effects that light produces on these volumes in real space. Modeling, this representation of volumes, can be done by means other than by claroscuro, as was the case in the Middle Ages.

the answer to your question is d. any light source appearing in a scene

explanation:

your word would be isle.

isle is an island or peninsula especially a small one.

if you add the letter "a" you get aisle, which is a passage between 2 rows of something like chairs, shelves, or something else.