One of the more reliable methods of determining regional climatic cond

(A) We know info is extracted from current glaciers, we can't infer anything about "glacial periods".
(B) No, glacial evidence tell us the TYPE of climate, whereas carbon dating tell us WHEN that climate was prevalent.
(C) We don't know whether similarities exist, we only know the climates of the different periods can be compared.
(D) We don't know how "continuous" pollen is, we don't know how often we find it in the glaciers.

(E) By POE, this is the only choice left. We know we can determine climate by examining frozen prehistoric pollen from plants, so certain plants must be reliable indicators of what type of climate/weather existed in a given region.

Since this is an inference question, we need to select an option which the above argument suggests, but not explicitly given in the argument.

(A) The earth has undergone several glacial periods. - argument just talking about determining climatic condition. We don't know if earth has undergone several glacial periods
(B) Radiocarbon dating can be corroborated by glacial evidence. -argument just mentions about determining the period using radiocarbon dating
(C) Similarities between prehistoric and contemporary climates do not exist. - Argument actually says opposite of this "By comparing such pollen samples with spores taken from modern vegetation"
(D) Pollen deposition is a fairly continuous process. -I would say this is an assumption in the argument. If its not continuous process then scientists may not be able to determine climatic conditions in certain prehistoric periods.
(E) Certain flora are reliably associated with particular climatic conditions. -The argument says "One of the more reliable methods of ....", so we can infer this option.

Option A is too much of an inference, the passage does not discuss the possibility of several glacial periods. It only discusses that weather conditions might have been different.
Option C is too strong by saying that similarities do not exist at all. The passage only discusses how to compare weather conditions using pollen data.

Having eliminated two out of the three options given, I guess, I'll go with B. The additional premise that starts with "Furthermore" is a good indication that we are flowing in the proper direction.

(A) we can't infer about "glacial periods".
(B) carbon dating tell us WHEN that climate was prevalent not type of climate
(D) don't know how often we find it in the glaciers.

(E) By POE, this is the only choice left.

climate can be determined by examining frozen prehistoric pollen,
certain plants must be reliable indicators of climate/weather existed in given region.

Lets solve this CR with the CR Bible strategies:

The structure of the argument is:
Premise + Conclusion + Additional Premise
(One of the more, by comparing) + (scientists can figure out) + furthermore

So, we can rearrnage the parts as:
Premise + Additional Premise + Conclusion

Premise: One of the more reliable methods of determining regional climatic conditions in prehistoric periods is to examine plant pollen trapped in glacial ice during ancient times.

Additional Premise: Furthermore, by submitting the prehistoric samples to radiocarbon dating techniques, we can also determine when certain climatic conditions were prevalent in that portion of the globe.

Conclusion:
Scientists can figure out approximately what the weather was like at the time of pollen deposition.

We can say an inference is like a Must be True statement based on the stimulus given. So, any answer choice rephrasing any of the above premise/additional premise/conclusion and avoiding new info will be the correct answer.

Now, lets check the given options:

(A) The earth has undergone several glacial periods. [No mention of Several glaciers. [New info based option. Incorrect]

(B) Radiocarbon dating can be corroborated by glacial evidence. [This is a Reverse case trap. Radiocarbon dating and glacial evidence are stated in the stimulus but in different context. Incorrect]

(C) Similarities between prehistoric and contemporary climates do not exist.
[This is Opposite case. Read the conclusion and additional premise. Incorrect]

(D) Pollen deposition is a fairly continuous process.
[No mention of such process. New info. Incorrect]]

(E) Certain flora are reliably associated with particular climatic conditions.
This is just the prephased version of the conclusion. Correct.

So, OA is E.

Can someone please explain what I'm missing here?

The stimulus talks about examining plant pollen. (E) talks about flora. How can (E) be the correct answer????

IMO (B) is the correct answer because this is exactly what the stimulus says:

Furthermore, by submitting the prehistoric samples to radiocarbon dating techniques, we can also determine when certain climatic conditions were prevalent in that portion of the globe.

+1 E

Choice E is correct because of this premise in the argument:

"By comparing such pollen samples with spores taken from modern vegetation, scientists can figure out approximately what the weather was like at the time of pollen deposition".
So, certain type of polen is related with some climatic conditions.
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(A) The earth has undergone several glacial periods- Out of Scope
(B) Radiocarbon dating can be corroborated by glacial evidence-
(C) Similarities between prehistoric and contemporary climates do not exist- wrong conclusion
(D) Pollen deposition is a fairly continuous process- Inconsequential
(E) Certain flora are reliably associated with particular climatic conditions- inference drawn from the premises as the whole passage is dependent on the fact that pollen from floras can indicate climate.

The basic approach to solve the inference questions is
1. Read the question
2. Work the argument- Identify the facts provided in the argument
3. Do effective process of elimination
A. Eliminate answers which have extreme language. Author is the boss of the argument, and any claim which is stronger than the claim made by the author can’t function as the right answer. The student should be always suspicious about answer choices which have words like all, always, none, only, must, never etc.
B. Eliminate answer choices which are beyond the scope of the argument.
Let’s try to attempt this question
It is an inference question
Let’s see the facts provided – Psychiatric problems in adults can be dealt with observing their childhood events. Some events during childhood leave a strong impression. The doctors can get a lot of clarity about patients’ insecurities and fears which will help in dealing with psychiatric disorders.
Now let us do process of elimination
A. This answer choice is out of scope
B. This answer is extreme in nature
C. The discussion does not draw similarities.
D. This answer choice is again out of scope.
E. This is supported from the facts provided. It serves as the right answer.
Keep practicing. Consistency is the key.
PythaGURUS Faculty Team
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Option B says the reverse. It says radiocarbon dating can be supported by glacial evidence, however from the argument it can be inferred that radiocarbon dating can be used to support glacial evidence

I think there are a few, easily missed words that separate the correct answer E from the wrong answer B.

First, this is an Inference question. Quite often the passage will be a collection of facts rather than the normal premise + author’s conclusion structure in other questions.

We are told there is a pretty reliable way to determine the climate conditions in prehistoric times.

The passage then goes out of its way to separate the next 2 facts.

1st, we are told that pollen trapped in ice is compared to “spores of modern vegetation. This can tell us approximately WHAT the weather was like when the pollen froze in the ice.

FURTHERMORE, the pollen can ALSO be submitted to radio carbon dating to determine WHEN such climate conditions occurred in that portion of the globe.

Both of these parts encompass “one of the more reliable” techniques for determining prehistoric climate conditions.

B says that one corroborates the other. We are not told whether this is true anywhere in the facts.

However, if E were not true, does it go against the Facts stated?

In order for this method of comparing frozen, prehistoric pollen to “modern spores on vegetation” to be reliable, it must be true that certain flora/vegetation are associated with certain climate conditions (to a reasonable degree).

How else could scientists compare these frozen pollen samples to modern plants and say, approximately, WHAT the climate conditions were at the time the pollen froze? The scientists are after all using the modern vegetation spores as a basis of comparison to make this determination.

E must be true for this entire process to be considered “one of the more reliable” ways to determine what the climate was at the time the pollen froze.

Posted from my mobile device

Tough question.

(A) The earth has undergone several glacial periods.
- Not necessary. There is nothing in the passage to suggest this.

(B) Radiocarbon dating can be corroborated by glacial evidence.
- Tricky. Notice that it is actually the other way round: glacial evidence can be corroborated by Radiocarbon dating.

(C) Similarities between prehistoric and contemporary climates do not exist.
- This could be a possible result of the investigation, but we don't know if this WILL be the result. So, this can't be inferred.

(D) Pollen deposition is a fairly continuous process.
- Not necessary. We don't know anything about continuity.

(E) Certain flora are reliably associated with particular climatic conditions.
- Correct. The whole point of the passage is to investigate the climatic conditions thru trapped pollen. This implies that certain flora (pollen) are reliably associated with particular climatic conditions.

Answer E.

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