Hm, I'm not quite sure. Is this a multiple choice question? If so, can you provide the answers?
The best answer here would be pencil.
Artists use pencil to make sketches and create studies. They then use these sketches and studies to create their final larger piece. They use pencil because it's quick, can be corrected, lightweight and easy to use. Before pencils artists would make charcoal drawings but once we had pencils it made sense to use them as they aren't messy like charcoal.
Green is the only true secondary color listed. The three main secondary colors are orange, purple, and green
Value The lightness or darkness of tones or colors. White is the lightest value; black is the darkest. The value halfway between these extremes is called middle gray. Space An element of art by which positive and negative areas are defined or a sense of depth achieved in a work of art .