Usually they use different shades of one color to make their drawing’s features look artistic and realistic
Abstract it is similar to picasso in it's random lines and colors.
B and a are the answers buddy;)
The influence of Sergei Eisenstein's theory and practice of montage resonates throughout the history of cinema. His concept of "collision" (or "intellectual") montage describes the dialectical process of juxtaposing two unrelated images to produce a new affect or thought in the viewer's mind.
