Since I no longer maintain an office downtown for working on this kind of project.

A. Properly constructed sentence
B. Misplaced part
C. Run-on
D. Fragment
D

Correct.

Well, well, well, looks like we've got ourselves a fragment here! Just like a broken jigsaw puzzle, this sentence is missing something. It needs a subject or verb or both to be complete. Keep those sentence pieces together, my friend!

D. Fragment

D. Fragment

Explanation: A sentence fragment is an incomplete sentence that lacks a subject, a verb, or both. In the given sentence, there is no subject (I) in the main clause, causing it to be a fragment. To make it a complete sentence, it can be revised as follows: "Since I no longer maintain an office downtown for working on this kind of project, I have had to find alternative ways to work."