Researchers have announced that the magnetic fields emitted

Question

Researchers have announced that the magnetic fields emitted by one manufacturer’s
security surveillance system,  of which type there are 200,000 worldwide, can interfere
with pacemakers and that  this interaction can bring on missed or irregular heartbeats,
nausea, breathlessness, dizziness, and even fainting.

A. of which type there are 200,000 worldwide, can interfere with pacemakers and
that
B. of which, worldwide, there are 200,000 of that type, and which can interfere with
pacemakers, and
C. of which type there are 200,000 worldwide, they can interfere with pacemakers
and
D. 200,000 of which type exist worldwide, interfering with pacemakers, and
E. 200,000 of that type existing worldwide and can interfere with pacemakers, and

OA is D. Some guru who can explain why D is ok and why the others are wrong? Tksvm

marshpa · Answer

I am sure that OA would be between D or E. But why D?? I can’t really explain however, I can tell the difference between D and E. E says systems existing currently and can interfere with pacemakers anytime.
D says systems exist at present, and are interfering with pacemakers continuously. 
I know my reasons are not very subtle here, but that is the best I can think of. I would appreciate if anyone can explain further.

peraspera · Answer

Very, very, extremely interesting. IMO, D is clearly wrong, because the verb 'to interfere' cannot be in present continuous form here.

Could you please post the source of this?
My answer is A.

Minheequang · Answer

In my opinion:

Researchers have announced that the magnetic fields emitted by one manufacturer’s
security surveillance system,  of which type there are 200,000 worldwide, can interfere
with pacemakers and that  this interaction can bring on missed or irregular heartbeats,
nausea, breathlessness, dizziness, and even fainting.

A. of which type there are 200,000 worldwide, can interfere with pacemakers and
that -->   there are  stands behind  of which type , sounding ungrammatical 
B. of which, worldwide, there are 200,000 of that type, and which can interfere with
pacemakers, and --> same error as (A), besides,  type  and  which  are seperated make the choice more incorrectly 
C. of which type there are 200,000 worldwide, they can interfere with pacemakers
and -->  same error as (A), also the first main clause is not completed when it is intefered by a new clause from "they ... pacemakers" 
D. 200,000 of which type exist worldwide, interfering with pacemakers, and -->  the first main clause is clearly completed: "the magnetic fields ... exist worldwide", then stands the sub-clause modifying for the first main clause: "interferring ... pacemakers" and finally the second main clause "this interaction... fainting" -->  the best  
E. 200,000 of that type existing worldwide and can interfere with pacemakers, and -->  while  that  can be as good as  which  in (D) to clearly modify for  surveillance system , the first main clause is not correctly constructed because there is no main verb for this clause: as if it were  existing , it would be ungrammatical; as if it were  can interfere , why did a conjuntion like  and  stand before such a main verb --> thus, this choice is incorrect

lordw · Answer

OA is D. Found it in the web

peraspera · Answer

Well, IMO the source is wrong, it cannot be D, as D clearly has grammar mistakes. I think it's A because A is 1) grammatically correct 2) concise and 3) correctly uses the parallel construction 'that...that...'. Could you prove that either A is wrong, or D is correct, with explanation? 8-)

bandit · Answer

D. Cannt explain though. Seems to the the best of the lot

bigtreezl · Answer

yup..would have picked A on test

pm4553 · Answer

What about "that" in A, isn't it an error?

D - 200,000 of which modifies "security surveillance system"

trainspotting · Answer

Friends, 
 It will be wrong to use "interfering" here as used in D..Whats the source of the OA???Of the ones left, A is the one that does not has the modifier error...My pick will be A...........

trainspotting · Answer

Dude "that" is used to create parallelism here.

A has announce that X and that Y..........You can find a number of examples based on this format............

Researchers have announced that the magnetic fields emitted

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