WRITING PROBLEM! HELP! CALLING x>700 on WRITING!

peteyflow
Thu, 23 Aug 2007 14:59:17 +0000

3.) Marie and Pierre Curie discovered radium but refused to patent the process they used nor otherwise profiting from the commercial exploitation of radium.

A) used nor otherwise profiting
B) had used nor otherwise did they profit
C) have used or otherwise to have profited
D) used or otherwise profited
E) had used or otherwise to profit

(I chose D. But it turned out to be E. Can somoene explain to me why it’s E? Thanks)