<p>I think I know this one. I remember this was CB's Question of the day a while back, and if I remember correctly, I got it wrong at first.</p>
<p>I think the key here is to seperate the sentences and judge them individually:
for example, would you say</p>
<p>A. "Carl Sagan refused PROFITING from later advancement in space exploration"? No, that's obviously not right.</p>
<p>B. Carl Sagan refused PROFIT from later advancement in space exploration"? Sounds OK.</p>
<p>C. Carl Sagan refused TO HAVE PROFITED from later advancement in space exploration"? Obviously wrong tenses.</p>
<p>D. Carl Sagan refused PROFITED from later advancement in space exploration"? No way.</p>
<p>E. Carl Sagan refused TO PROFIT from later advancement in space exploration"? Sounds OK.</p>
<p>So now you're down to 2 that sound OK, B and E. Since "had designed" is the same in both, the problem must lie with how he refused to profit --
E makes more sense because it follows the structure of the sentence; you're saying </p>
<p>CARL SAGAN REFUSED TO ACCEPT PRAISE FOR HIS PLANS
CARL SAGAN REFUSED TO PROFIT</p>
<p>With B on the other hand though, what you're basically saying is</p>
<p>CARL SAGAN REFUSED TO ACCEPT PRAISE FOR HIS PLANS
CARL SAGAN DID NOT PROFIT</p>
<p>And you say this without cleanly transitioning - Carl Sagan goes from doing doing an action, REFUSING, to "not profitting". It's not a good structure.</p>
<p>E on the other hand is clean - he refuses praise, he refuses profit.
I think it's E.</p>