CR: engulfing of one organism by another

[divineacclivity]

Some types of organisms originated through endosymbiosis, the engulfing of one organism by another so that a
part of the former becomes a functioning part of the latter. An unusual nucleomorph, a structure that contains DNA
and resembles a cell nucleus, has been discovered within a plant known as a chlorarachniophyte. Two versions of
a particular gene have been found in the DNA of this nucleomorph, and one would expect to find only a single
version of this gene if the nucleomorph were not the remains of an engulfed organism’s nucleus. Which one of the
following is most strongly supported by the information above?
A. Only organisms of types that originated through endosymbiosis contain nucleomorphs.
B. A nucleomorph within the chlorarachniophyte holds all of the genetic material of some other organism.
C. Nucleomorphs originated when an organism endosymbiotically engulfed a chlorarachniophyte.
D. Two organisms will not undergo endosymbiosis unless at least one of them contains a nucleomorph.
E. Chlorarachniophytes emerged as the result of two organisms having undergone endosymbiosis.

source: 700-800
OA: E

All options sounded absolutely wrong to me & at last I chose B because the argument says "Two versions of
a particular gene have been found in the DNA of this nucleomorph & concluded the engulfing" => they looked nowhere else for a 3rd version of a gene; they found 2 in nucleomorph & concluded that's it, one of two organisms engulfed the other => the information, if atall, bout the other organisms would be found in nucleomorph.

Please help me understand why it is E. Chlorarachniophytes might already be there but one with 2 versions of genes might be a rare one, which is fine but the paragraph nowhere says Chlorarachniophytes itself emerged bcs of 2 versions of genes and a singled version never existed.

[tim]

As per the forum rules, we need a verifiable source for the problem before we can deal with this question. If the question is not one of ours or one that is copyright-free, we will have to delete the question..

[divineacclivity]

hey,

It should be copy right free because it is freely available at:
http://gmatclub.com/forum/download.php
I didn't use any hacks. Please do let me know if this material is not copy-right free.

thanks in advance

[tim]

you're going to have to do more to convince us that this question is legal for us to discuss. just because another website has questions on it does not mean that they are legally posting them. i am not aware of any content that gmatclub writes itself, so until i am informed otherwise anything available from their site will need a further source. please understand we're just trying to obey the law and respect people's intellectual property..