Rattlesnakes

Question

The folktale that claimes that a rattlesnake's age can be determined from the no of sections of its rattle is false, but only because the rattles are brittle and sometimes partially or completely break off. So if they were not so brittle, one could reliably determine a rattlesnake's age from the no of sections in its rattle, because one new section is formed each time a rattlesnake molts.

Which one of following is assumption that argument requires in order for the conclusion to be properly drawn?

(a) rattlesnake molts exactly once a yr
(b) Rattle in rattlesnakes of different species are identical in appearance
(c) rattlesnake molts more frequently when young than when old
(d) brittleness of rattlesnake's rattle is not correlated with the length of rattlesnake's life
(e) rattlesnakes molt as often when food is scarce as they do when food is plentiful

riteshgupta1 · Answer

A is my choice.

gotoknow3 · Answer

one more A

ranga41 · Answer

IMO  E  is the answer, A is not correct because it could molt once every 2 years and its age could still be determined from the number of rattles (multiplied by 2), the assumption is it molts periodically not necessarily every year, but If E is false then the molting will not be periodic and age will be a factor of food availability...

Darth_McDaddy · Answer

I will go with A.

Ranga, You have reasoned out your support for E quite well, but choice E still misses out a key point, and that is - periodicity of molting. The molting should take place in regular intervals, but E gives you no clues that molting takes place regularly. While it is true, that molting can take place once in two years too, but A clearly states that molting takes place regularly on an annual basis.

Thus A.

PS - Besides, isn't age an annual, yearly feature?

ranga41 · Answer

Let us wait for the OA.

(e) rattlesnakes molt  as often  when food is scarce as they do when food is plentiful

IMO  as often  is enough to represent the periodicity of molting.

Ofcourse age is annual but molting need not be, I felt to say that the argument assumes the molting takes place every 1yr is very preposterous.

riteshgupta1 · Answer

Unless you have an exact count of exactly how many section are formed each time a rattlesnake molts, you really can not tell the age.

D says, they do quite often when food is scarce.
Ok, lets say the food scarcity is dispersed, then how many times he does when it is plentiful and how many times when not plentiful and how do you that in the life span of snake, how many times they had food scarcity.

I think A says it all.

Bhai · Answer

D.

ronybtl · Answer

ranga41: You are correct. The OA is E.

Found this qn "snaky" and at first, could not understand why E was the answer until i read responses of all in the forum.

I made the mistake of assuming that , in order to ascertain the age of the snakes, we must know that they molt once a yr. Therefore, i picked A. 

However, Ranga was correct that, as long as we can ascertain the periodicity of the molting, we can ascertain the age . Answer E nails down the periodicity element and therefore is the correct ans.

D is incorrect. D implies brittleness may be correlated to factors other than age. However, it does not sppt the conclusion. Also, conclusion assumes that the rattles are not so brittle.

C would undermine conclusion. because it destroys the periodicity element. B is irrelevant to conclusion.
Thks

Rattlesnakes

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