TTgwd31-13 -- need correct question -- B or D? NN plz help

Here is what I have, the key is C but I chose A since C clearly short of "by". Someone saying this question has

typo in sen4sun 22 version of GWD. Please help who has correct question?

And also, in E: is but and nevertheless redundant?

Thx

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13. GWD31-Q13

Dolphins lack vocal cords, nevertheless creating sounds: a complicated

system of whistles, squeaks, moans, trills, and clicks are produced by

sphincter muscles inside the blowhole

A.                 nevertheless creating sounds; a complicated system of whistles,

squeaks, moans, trills, and clicks are produced by

B.          nevertheless creating sounds; they produce a complicated system of

whistles, squeaks, moans, trills, and clicks with

C.          but they do create sounds, producing a complicated system of whistles,

squeaks moans, trills, and clicks being produced

D.          but they do create sounds, a complicated system of whistles, squeaks,

         moans, trills, and clicks being produced  

E.           but nevertheless creating sounds; a complicated system of whistles,

squeaks, moans, trills, and clicks produced by

Plz help !!

any help?

D

Tha answer is E but I chose B.

Some say the original question has semicolon in B and E and the one in sen4sun22 has colon in B and E. Anyone has the correct original question?

And also, is "but" and "nevertheless" redundant in E?