Double-blind techniques should be used whenever possible in scientific experiments. They help prevent the misinterpretations that often arise due to expectations and opinions that scientists already hold, and clearly scientists should be extremely diligent in trying to avoid such misinterpretations.
Which one of the following most accurately expresses the main conclusion of the argument?
(A) Scientists’ objectivity may be impeded by interpreting experimental evidence on the basis of expectations and opinions that they already hold.
(B) It is advisable for scientists to use double-blind techniques in as high a proportion of their experiments as they can.
(C) Scientists sometimes neglect to adequately consider the risk of misinterpreting evidence on the basis of prior expectations and opinions.
(D) Whenever possible, scientists should refrain from interpreting evidence on the basis of previously formed expectations and convictions.
(E) Double-blind experimental techniques are often an effective way of ensuring scientific objectivity.
A. This is a supporting fact. It backs up the recommendation to use double-blind methods by highlighting how they reduce bias.
B. Correct. This is the main conclusion. It’s marked by the word “should,” and the rest of the passage offers reasons to support it—specifically, how double-blind techniques help avoid biased interpretations.
C. This wasn't stated in the argument. Merely considering bias isn’t equivalent to using a double-blind method, so this can’t be the conclusion.
D. This is another piece of supporting evidence. It illustrates the kind of misinterpretation double-blind techniques are meant to prevent.
E. The author doesn’t claim that double-blind methods guarantee objectivity—only that they help promote it. More importantly, this is a supporting point, not the main conclusion.
