GMAT Sentence Correction (SC) | Re: #Top150 SC: The Middle Stone Age, extended for 200,000 years from

There is no valid answer to this question. First off, the Middle Ages weren't "extended" by anyone or anything. This alone would leave only D, but D is not a complete sentence. (There's no main verb for The Middle Ages.) Here's a well-known official Q that deals with extended/extending: http://gmatclub.com/forum/scientists-ha ... -9394.html

If