in E, Even though and but, both show contradiction. But use of only one should be sufficient.
Rule out E.
pick D.

we need past perfect.
time frame 1: till the success, before opting out.
time frame 2: the opting out and after.

Q According to the second paragraph of the passage (lines 20-42), Whig propaganda included the assertion that A. women should enjoy more political rights than they did B. women were the most important influences on political attitudes within a family C. women's reform activities reminded men of imp...

During the past five years, more than 5000 Maltanians have drowned in boating accidents. Figures released by the country's Boating Association show that ninety percent of the victims were not wearing life jackets at the time of their accidents. This information indicates that by wearing life jacket...

If # denotes one of two arithmetic operations, addition or multiplicatio, and if k is an integer, what is the value of 3 # k? 1) 2 # k =3 2) 1 # 0 = k OA is A. I answered E. Please explain your reasoning. I think you forgot to consider that K is an integer and hence, for stmt. I: k can not be 3/2.

The premise clearly tells that scientists need an oxygen free environment to test their hypothesis. so any option that taks about oxygen free environment and at the same time removes the problem(= that fireflies die in oxygen free environment) faces by the scientists, would do the trick. Hence, IMO ...

Further to the above explanations, don't you think that the use of word only makes the option too extreme.