The correct answer is option D ("The physical body is beautified at the cost of the soul's neglect").
The figurative language in this poem serves to contrast the physical, ephemeral existence of the body in opposition to the transcendent and therefore most important nature of the soul. The author likens the body to a building that the soul inhabits for only a little while in the grand scheme of things. Then he goes on to question the futility of the efforts we make in order to appear beautiful in the outside, at the expense of our actual soul's well being inside of us.
This idea is perhaps best illustrated on the following lines: "Why dost thou pine within and suffer dearth; Painting thy outward walls so costly gay?; Why so large cost, havins so short a lease".
Hope this helps!