IMO, there are at least two splits that you can use to eliminate D) and E) in 63.
First, the sentence starts with a modifier "Unlike emergency calls that travel through regular telephone lines" which should precede immediately before a noun. D) "and thus blah blah", incorrect. In addition, D) breaks the two verbs with the same subject "emergency calls" without probable reason, incorrect. E) "thus automatically informing blah blah" is another modifier, incorrect.
Second, ignoring the problems mentioned above, D) and E) both incorrectly compare "emergency calls" with "emergency operators", resulting nonsensical sentences.
-- by 会员 silent7706 (2010/7/14 9:40:07)
95, E so that 句型 很明显 ,D选项,我觉得读不通。。。。。。63, 只有A B 里头选 A where 的状语从句中的their 指代不明确
-- by 会员 vickyying811 (2010/7/14 10:52:28)