LSAT reasoning problem help...

[Xyo II]

Originally posted by: blipblop
The folktale that claims that a rattlesnake's age can be determined from the number of sections in 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 simply from the number of sections in its rattle, because one new section is formed each time a rattlesnake molts

which one of the following is an assumption the argument requires in order for its conclusion to be properly drawn?

A. Rattlesnakes molt exactly once a year

B. The rattles of rattlesnakes of different species are identical in appearance

C. Rattlesnakes molt more frequently when young than when old

D. The brittleness of a rattlesnake's rattle is not correlated with the length of the rattlesnake's life

E. Rattlesnakes molt as often when food is scarce as they do when food is plentiful.

Can someone explain to me why E is the correct answer?

The argument IS that Rattlesnakes molt exactly once a year (so you would be able to determine their age), but the argument relies on rattlesnakes having plenty of food every year. I would suppose that they would molt less when the food is scarce, so it might not necessarily be every year.

Since they may shed their skins several times a year depending on food supply and growth rates and since the rattle can and does break, there is a little truth to the claim that one can tell a rattlesnake's age from the number of beads in its rattle.

I guess I was right.