It can be inferred from the author's discussion of Pseudomonas fluorescens bacteria that which one of the following w...

Mehran July 15, 2018

Hi @EmilyMarieMenendez, thanks for your post. "Inference" means "must be true" - there must be textual support in the stimulus (for Logical Reasoning questions) or the passage (for Reading Comprehension questions) for the correct answer. Often, students are able to narrow down the answers to two choices, then get stuck. At this juncture, they lose sight of the need to select the textually-supported answer, and make a mistake. If you are struggling on these questions, you may find it particularly helpful to return to the text before you select your ultimate answer.

Hope this helps. Please let us know if you have any additional questions.

Steph January 6, 2019

Hi. Can you please explain why C is the correct answer and not any of the other choices?

Ravi January 7, 2019

@Steph,

Happy to help! The question is asking us to infer something from the
passage that which of the following would be true of crops impervious
to parasitical organisms. The discussion about P. fluorescens bacteria
occurs primarily in the first paragraph, so that's where our attention
should be focused.

Let's say that the crop in question is corn, and we have a type of
corn that is impervious to parasitic organisms. Based on the content
of the first paragraph, what was the purpose of P. fluorescens? Well,
it's noted that it's a bacterium that's antagonistic to a number of
harmful phytopathogens/parasitical organisms, and there is evidence
that it can help improve crop yields by combating the growth of the
parasitical organisms.

Answer A is incorrect because P. fluorescens could still be present in
the soil in this hypothetical scenario; they just wouldn't help much
since the corn is already impervious to the parasitic organisms.

Answer B is incorrect because we have no evidence from the passage
that P. fluorescens would crowd out and exclude other crop plants.
There is no support for this answer, so we can't infer it. We can get
rid of B.

Answer C says, "their yield would not be likely to be improved by
adding P. fluorescens bacteria to the soil." If the soil in our
hypothetical is resistant to parasitic organisms (which it is since
we're told that it is in the stimulus), then this would be true
because the whole purpose of P. fluorescens is to combat the parasitic
organisms. If they don't need to be combated, then how will P.
fluorescens improve yield? It won't, so this is our correct answer
choice.

Answer D is incorrect because we have no reason that they would
necessarily mature more quickly. What if P. fluorescens were put with
the crops that were susceptible to parasitical organisms? Secondly, we
have no idea what "maturity" means within the context of these crops,
so that's another reason why this can't be inferred.

Answer E is incorrect because we have no reason to believe that the
levels of phytopathogenic bacteria would be higher compared with other
crop plants. Why would they be higher if the crop is resistant to
these phytopathogens? We can't infer E, so it's out.

Does this help? Let us know if you have any more questions!