How does an imaginary rectangle around an object help?

Correct answer: Establishing main proportion and placement

The governing concept is construction through a bounding shape. An imaginary rectangle gives the object a preliminary height, width, and position on the page. The artist can compare the object's parts with these limits before refining the contour, which improves proportion and placement. It does not erase shadows, alter texture, or select colour, so option A is the only suitable answer.