What step did the artist clearly use when drawing this image?

Question

Responses

two vanishing points
two vanishing points - not selected, this is the correct answer

only orthogonal lines
only orthogonal lines - no response given

imagery in the background larger than in the foreground
imagery in the background larger than in the foreground - no response given

imagery in the foreground lighter than in the background

Answer 1

imagery in the foreground lighter than in the background - no response given