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
在jinni MM的GWD分类里面看到这道题说D the best，但是我觉得选A，announced了两方面的内容，一是magnetic fields会影响pacemakers，二是，这个interaction能产生一系列的状况。A在结构上也平行地用两个that，D中用把fields和interaction并列作为分名的主语，逻辑上有点说不过去，请指教！ | 
