Sentence Rearrangement and Paragraph Organization

Which of the following should be the THIRD sentence after rearrangement?

Directions: Rearrange the following five sentences in the proper sequence to form a coherent paragraph, and then answer the question.

(i)     It remained for the Greeks fully to develop the lintel.
(ii)    The Egyptians in their constructions did little more than to place enormous stones on end, and pile one huge block upon another.
(iii)   The upright or supporting member may be said to have been in Egyptian architecture the predominant one. 
(iv)   They used many columns placed close together: the spaces which they spanned were inconsiderable.
(v)    A vertical line therefore may be taken as the simplest and most abstract symbol of Egyptian architecture.