Whales originated in the freshwater lakes and rivers of ancient - 2

I think ,we are only interested abt whales between 60 MN and 50 MN.
All options other than A seem to be irrelevant to me

The question stem is:
"Which of the following is most strongly supported by the information given?"

So you need to find the option that is supported BY the argument. The argument supports one option. Hence, that option would be the inference.

The word "support" could indicate either strengthen or inference question type. If the argument supports the option, you are looking for an inference. If you need the option to support the argument, you are looking for a strengthener.

According to PowerScore CR Bible question properties, this question should be categorized and handled as a "Must be True" question.

True. 'Inference' and 'must be true' are same question categories.

Can anyone provide a detail solution to this question.
Thanks

A) Correct. The capacity to swim in salt water for long periods of time did not emerge until circa 50 million years ago. So we would not expect to find whales outside of their natural habitat, across saltwater oceans.

B) "None" is a strong word. Perhaps one such fossil was found.

C) Not necessarily true--we have no basis to make that conclusion.

D) Likewise. We have no basis to make this conclusion.

E) This choice is perhaps true in the real world sense, but the stimulus does not make such a claim.

The reason option A is supported is because if it were true that whales had to constantly return to freshwater lakes then it is unlikely that they would live on continents that are far aware from a freshwater source which is basically what A is saying

Moderators please change the Tag from Strengthen to Inference.

___________________________________
Done. Thank you.

Hello Verbal Experts,

Can you please throw light on why option B is wrong.

Also, per the GMATPrep, Option B does not contains the word "none. It says "very few".

Option B - Among whale fossils that date from later than about fifty million years ago, VERY FEW are fossils of whale species that drank only fresh water.

I'm unable to eliminate option B: If Whales developed Kidneys 50 million years ago, all the fossils of whales after 50 million would be those of salt water whales. please help

Its not necessary that if whale have kidneys to digest salt water they can never reside in fresh water or vise versa.
B states the whales fossils after 50 million years ago don't have trace of drinking only fresh water. The conclusion can be held true for the whales dated before 60 million years ago, not 50 because they were migrating to survive hence drinking both water type. But we can't say the fossils Or the whales dated after 50 millions were migrating too.they don't have any reason. They can survive in both fresh or salty water. Hence drawing conclusion that they drank both is speculation not supporting the passage. Hence its wrong.

Posted from my mobile device

Why can a non-salt water whale not get stranded in a salty ocean and become fossilized? They have to return frequently to fresh water in order to drink but it's not guaranteed that all will make it back...

Posted from my mobile device

Surely, They could stranded and become fossilized. The argument is only concerned about that for whales to drink clean water ( in order to survive), they had to return to fresh water sources. It doesn't affect our conclusion if some whales could not come back and died .


I hope it answers your query.

KarishmaB I just have one doubt which none of the expert replies have addressed till now.

In option B- " Among whale fossils that date from later than about fifty million years ago, none are fossils of whale species that drank only fresh water."

Does "later than fifty million years ago" mean something like 40 million years ago from the present or something like 70 million years ago from the present? Got confused by this and hence couldnt solve the question right.

Imagine a timeline. 50 million years ago is a point on that timeline. Later than that means the time after that. So 40 million years ago, 30 million years ago, today...

Understanding the argument - one piece of advice. Read every word of the argument and answer choices carefully. If we do that, this question is ok. We are given some facts, and we need to find well-supported information.

Option Elimination

(A) Fossils of whale species dating from between sixty million and fifty million years ago will not be found on continents that were at the time separated from ancient Asia by wide expanses of ocean. - It says sixty million and FIFTY million. It talks about the 10 million years of the initial period when they didn't have special kidneys. You can cross out this option if you read the FIFTY and FOURTY million. But if we read well, this option is perfect.

(B) Among whale fossils that date from later than about fifty million years ago, none are fossils of whale species that drank only fresh water. - They developed special kidneys, but it doesn't mean 100% of them suddenly start drinking salt water. We are not sure. The "might be true" is the wrong option as we can't say with 100% certainty from the argument.

(C) Fossils of whale species that drank fresh water will not be found in close proximity to fossils of whale species that drank salt water. - We are not sure. The "might be true" is the wrong option as we can't say with 100% certainty from the argument.

(D) The earliest whales that drank salt water differed from fresh-water-drinking whales only in their possession of specialized kidneys. - The argument talks about kidneys, but does that mean there are no other distinctions? We don't know. The skin may be different as well. We are not sure. The "might be true" is the wrong option as we can't say with 100% certainty from the argument.

(E) Between sixty million and fifty million years ago, the freshwater lakes and rivers in which whales originated were gradually invaded by salt water. - Argument doesn't even talk about it. We are not sure. The "might be true" is the wrong option as we can't say with 100% certainty from the argument.