A tree’s age can be determined by counting the annual growth rings in its trunk. Each ring represents one year, and the ring’s thickness reveals the relative amount of rainfall that year. Archaeologists successfully used annual rings to determine the relative ages of ancient tombs at Pazyryk. Each tomb was constructed from freshly cut logs, and the tombs builders were constrained by tradition to use only logs from trees growing in the sacred Pazyryk Valley.

Which one of the following, if true, contributes most to an explanation of the archaeologists’ success in using annual rings to establish the relative ages of the tombs at the Pazyryk site?

(A) The Pazyryk tombs were all robbed during ancient times, but breakage of the tombs seals allowed the seepage of water, which soon froze permanently, thereby preserving the tombs’ remaining artifacts.
(B) The Pazyryk Valley, surrounded by extremely high mountains, has a distinctive yearly pattern of rainfall, and so trees growing in the Pazyryk Valley have annual rings that are quite distinct from trees growing in nearby valleys.
(C) Each log in the Pazyryk tombs has among its rings a distinctive sequence of twelve annual rings representing six drought years followed by three rainy years and three more drought years.
(D) The archaeologists determined that the youngest tree used in any of the tombs was 90 years old and that the oldest tree was 450 years old.
(E) All of the Pazyryk tombs contained cultural artifacts that can be dated to roughly 2300 years ago.

Pls explain
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Neelabh Mahesh

A tree’s age can be determined by counting the annual growth rings in its trunk. Each ring represents one year, and the ring’s thickness reveals the relative amount of rainfall that year. Archaeologists successfully used annual rings to determine the relative ages of ancient tombs at Pazyryk. Each tomb was constructed from freshly cut logs, and the tombs builders were constrained by tradition to use only logs from trees growing in the sacred Pazyryk Valley.

Which one of the following, if true, contributes most to an explanation of the archaeologists’ success in using annual rings to establish the relative ages of the tombs at the Pazyryk site?

(A) The Pazyryk tombs were all robbed during ancient times, but breakage of the tombs seals allowed the seepage of water, which soon froze permanently, thereby preserving the tombs’ remaining artifacts.-----Not Relevant ....not providing any iformation regarding calculating the age of the tomb-eliminate
(B) The Pazyryk Valley, surrounded by extremely high mountains, has a distinctive yearly pattern of rainfall, and so trees growing in the Pazyryk Valley have annual rings that are quite distinct from trees growing in nearby valleys.----It provides an explanation in calculating the age of the tomb --Hold it
(C) Each log in the Pazyryk tombs has among its rings a distinctive sequence of twelve annual rings representing six drought years followed by three rainy years and three more drought years.--Odesnot provide explanation in calculating the age of the tomb --Eliminate

(D) The archaeologists determined that the youngest tree used in any of the tombs was 90 years old and that the oldest tree was 450 years old.--Eliminate..not relevant
(E) All of the Pazyryk tombs contained cultural artifacts that can be dated to roughly 2300 years ago.--Eliminate..is not providing any explanation regarding the calculation of the age of the tomb



Like to go for "B"

could anybody explain this one?
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If I had to say something, I would say B...
OA is C. Could anybody elaborate on this, please??
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B cannot be used to determine the age of tombs because only the size of rings is related to the amount of rainfall. And the size of rings cannot be used to determine age. Rather we need the number of rings (because 1 ring is equal to 1 year as stated in the premise) along with the amount of rainfall to determine the number of years.

Hence C.

In order to date the tombs relatively to each other, you need to find a common date to start from. If you don't, you only know that for example a tree used for a tomb was 90 years old, while a tree used for another tomb was 120 years old.
This common date from which you can date tombs is provided by the specific pattern mentioned by answer C.
All other answers do not provide any info on how to relate a tree's age to another tree's age.
Thus C.