Answer:
A. He drew a horizon line to show where the sky and earth appear to meet.
B. He used a vanishing point to draw objects that run horizontally across the painting.
D. He used orthogonal lines to draw the sides of objects that run towards the vanishing point
Explanation:
A painting with one-point perspective contains only one vanishing point on the horizon line, which in the case of da Vinci's <em>The Last Supper</em> is the line where the sky and earth meet. Thanks to this perspective, things shown in the painting appear to get smaller as they get further away. Objects feel three-dimensional, despite being shown on a two-dimensional surface.
The picture below shows how da Vinci use one-point perspective. We can see how he used a vanishing point to draw objects that run horizontally across the painting, as well as the orthogonal lines to draw the sides of objects that run towards the vanishing point.
