The question below comprises four scattered segments of a paragraph. Identify from among the four choices the sequences that correctly assemble the segments and complete the paragraph.

A) this is a major reason that the Indus culture surely one of the greatest of the ancient world, has remained vexingly obscure.

B) like the people of Mesopotamia, the Indus people also had a writing system.

C) despite the efforts of many scholars, however, the symbols have yet to yield a credible sentence.

D) archaeologists have unearthed thousands of examples of the script.