#19 - Concept Reference, Must Be True, Subject's Perspective

[Dana D]

Hey Zoe Zoe,

This is a must be true question, so we are looking for an answer choice which is explicitly supported by the passage. Answer choice (C) is incorrect for the exact reason you cited – you assumed that the altered bacteria were also more effective, despite the passage not saying that. It’s also important to note that the proponents of this use of altered bacteria were not comparing its effectiveness or safety compared to Pseudomonas fluorescens bacteria. They argue that altering the harmful bacterial phytopathogens could work similarly to Pseudomonas fluorescents, but there are no explicit comparisons of the safety or effectiveness of the two methods.

[anotherwolf]

Hi,

Could you please explain why C is incorrect?

The genetically altered version satisfies both "safer" and "more effective." In line 44, "thereby rendering it safer than phytopathogen from which it was derived." I assume the altered version is also more effective since it could avoid frost by crowding out the original phytopathogen (line 36).

Thank you.

"More effective" seems to be a little off, but I thought "used in earlier experiments" is what makes this choice incorrect. Perhaps derived from the bacteria does not equate to used in earlier experiments.

[Adam Tyson]

I see two additional problems with that answer, anotherwolf. The first is that the passage does not say that it is "much" safer, only that it is safer. The second is that it doesn't say that it is more effective. Maybe it is, maybe not. More effective at doing what, exactly? We're talking about a phytopathogen, which is a harmful form of bacteria, and a genetically altered version that crowds out the harmful one. What does this have to do with being effective? All we know about the bad pathogen is that it causes frost damage; if that's all it does, then the altered one is actually less effective, since it doesn't do what the naturally occurring one did. And yes, there is no indication that there were earlier experiments with the natural version.

One more thing: the question begins with the phrase "according to the passage." That means the correct answer will either directly quote the passage, or else it will paraphrase the text. The correct answer will be explicit in the passage, and not be an inference drawn from evidence in the passage. We're looking to quote the text here, and answer C cannot be found in that text.