Hollyhocks raised in greenhouses by the Texas University botany school

Answer Option C.

Ques: Which of the following, if true, would best support the conclusion drawn in the passage?

Options A,D, and E were negated as none of them were effective.
between Option B and C, finally with C as it gives more strong conclusion.

This a strengthen the argument type of question. The last sentence of the passage is the conclusion of the argument. In order to support the conclusion, we need to identify an option that adds information to show that the hollyhocks' growth rate will indeed be greater after transplantation from Florida University to the Texas University’s greenhouses than it would have been if the plants had been left where they were.

Most ‘strengthen the argument’ questions have one or two options that weaken the conclusion instead of supporting it. Option A is one such option that indicates that the growth rate of the hollyhocks, instead of increasing, might actually be lowered and might further affect the growth rate of the hollyhocks that are already in the greenhouses. So, Option A is wrong.

Option B does support the conclusion in a vague manner, but does not mention that the hollyhocks that are transplanted have come from Florida University. They could have come from anywhere. So, Option B does not provide evidence strong enough to support the conclusion.

Option D also weakens the argument in a roundabout way by stating that the growth rate of the hollyhocks grown by Florida University has been increasing. This indicates that the growth rate would be high even if they weren’t transplanted to the greenhouses of Texas University, thereby weakening the argument that the greenhouses are responsible for the improved growth rate.

Option E is irrelevant because it discusses transplantation in the reverse order.

Option C does state that temperatures in the greenhouses are more consistent than in the sites where hollyhocks are grown in Florida university; this is extra information that confirms that the growth rate is greater due to a specific reason. The temperatures are artificially controlled and kept consistent in a greenhouse and this process helps the growth rate of the hollyhocks.

Therefore, Option C adds most support to the conclusion.

Jayanthi Kumar.

OE:

Conclusion: If a hollyhock originally planted outside by the Florida University botany school is transplanted and moved to the greenhouses run by the Texas University botany school, the hollyhock's growth rate will be greater than it would have been.

Premise: Hollyhocks raised in greenhouses by the Texas University botany school grow an average of 20 centimeters per year, while hollyhocks raised outdoors by the Florida University botany school grow an average of 14 centimeters per year. The annual growth rate of the average hollyhock is 17 centimeters per year.

Assumption: (1) It’s not a coincidence. It’s not a coincidence that hollyhocks raised in greenhouses at Texas University grow an average of six centimeters per year more than those raised outside at the Florida University botany school.

(2) There’s no other cause. There’s no other cause for the additional growth other than the fact that the hollyhocks were raised in greenhouses.

This is a strengthen question, as evidenced by the phrase Which of the following…would best support the conclusion. The passage uses the premise that Hollyhocks raised in greenhouses by the Texas University botany school grow an average of 20 centimeters per year, while hollyhocks raised outdoors by the Florida University botany school grow an average of 14 centimeters per year, and the annual growth rate of the average hollyhock is 17 centimeters per year. The passage concludes that If a hollyhock originally planted outside by the Florida University botany school is transplanted and moved to the greenhouses run by the Texas University botany school, the hollyhock's growth rate will be greater than it would have been.

This passage contains a causality reasoning pattern, which can be identified by the fact that a specific outcome is being attributed to a specific cause. In this case, the annual growth rate of the…hollyhock is attributed to the location in which it is raised. Hollyhocks raised in greenhouses by the Texas University botany school grow faster than those raised outdoors by the Florida University botany school. Because of this difference, the author concludes that a hollyhock moved to the greenhouses will grow faster than it would have if not moved. The standard assumptions of an argument containing a causality reasoning pattern are that it’s not a coincidence and there’s no other cause. In order to strengthen an argument containing a causality reasoning pattern, the correct answer choice needs to demonstrate that it is not a coincidence, or rule out the possibility of another cause. In other words, it’s not a coincidence that Hollyhocks raised in greenhouses by the Texas University botany school grow an average of 20 centimeters per year, or there’s no other cause for the additional growth other than the fact that the hollyhocks were raised in greenhouses.

Choice A: No. The fact that overcrowding may lower the average growth rate of the hollyhocks there weakens the conclusion that If a hollyhock originally planted outside by the Florida University botany school is transplanted and moved to the greenhouses run by the Texas University botany school, the hollyhock's growth rate will be greater than it would have been.

Choice B: No. The mention of Thirty percent of the hollyhocks is out of scope. The passage concludes that the hollyhock's growth rate will be greater than it would have been, not a portion of the hollyhocks.

Choice C: Correct. This answer provides information that supports the conclusion by providing an explanation for the differing growth rates. Temperatures that favor hollyhock growth rates are more consistent [at] Texas University than…at Florida University supports the idea of a causal link between the location and the growth rate, which strengthens the conclusion that the transplanted hollyhock's growth rate will be greater than it would have been.

Choice D: No. The fact that the growth rate of hollyhocks grown by Florida University has been rapidly increasing weakens the conclusion that If a hollyhock originally planted outside by the Florida University botany school is transplanted and moved to the greenhouses run by the Texas University botany school, the hollyhock's growth rate will be greater than it would have been.

Choice E: No. The fact that hollyhocks…transplanted from Texas University greenhouses to outdoor sites at Florida University have roughly equal growth rates to hollyhocks that remain planted in Texas University greenhouses weakens the conclusion by suggesting that there is a cause other than location for the faster growth of these plants.

The correct answer is choice C

(C) is the correct answer.

We have to strengthen the argument that if the hollyhocks from Florida University, where the growth rate is 14 cms, were to be transplanted to Texas University greenhouse conditions, their growth rates would be greater (presumably similar to the growth rates of 20cms of the hollyhocks in Texas University). Let us go through the options one by one --

A -- this is sort of the opposite of what we are looking for. This seems to indicate that the overall growth rate of the Floridan University hollyhocks may not reach 20cms. Eliminate

B -- This one is a bit more promising; However, 30% is still a pretty insignificant figure, statistically speaking. We would have been a bit more confident in the argument's conclusion had the option mentioned that the growth rate(s) exceeded 20cms for at least 50%+ of the hollyhocks transplanted. Eliminate

D -- Well, this one says that it is better not to transplant the hollyhocks from Floridan University conditions to Texas University greenhouses, since the growth rate has been increasing anyways in recent years. Again, we are looking for an option that says that it is a good idea to transplant. Eliminate

E -- Irrelevant. We are not concerned with what happens to the growth rates of the Texan University hollyhocks. Eliminate

(C) is correct as it elaborates how adverse conditions at Florida University may have stilted the growth rates of hollyhocks there, preventing them from growing to their full size, and how the favorable conditions at Texas University would help overcome this obstacle.

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