From the Window of an Office on a Skyscraper's 90^th

Multiple Choice

From the window of an office on a skyscraper's 90^th floor,taxis on the street look tiny.Of course,you know they are not toy cars;you are just really far up.This example illustrates the _____ cue of _____.

A) monocular;relative size
B) binocular;relative size
C) monocular;texture gradient
D) binocular;texture gradient