Critical Reasoning

In the ruins of the city-state of Assur, in Ancient Assyria, archaeologists found dried goatskin dating back 3800 years. Analysis of the goatskins showed that they had an unusual pH level that was no lower than that of the calcium carbonate mixture produced by grinding cowrie shells, the most common seashells found on the shore of the Tigris river that runs through Assur. Some believe that this is evidence the Assyrians engaged in the practice of "liming" animal skins: soaking them in alkaline solutions made from crushed seashells in order to create parchment that could be traded with nearby civilizations.

Which of the following, if true, would, together with the information above, provide the best evidence for the claim that the dried goatskins are evidence that the Assyrians engaged in the practice of "liming" animal skins?

1. The calcium carbonate from the cowrie shell is the most common chemical used in modern-day "liming" of parchment and leather.

2. Apart from the Assur discovery, there is reliable evidence that some ancient civilizations, such as the Babylonians, practiced "liming."

3. The goatskins were found in huts that contained equipment known to have been used by Assyrian tradesmen and chemists.

4. Calcium carbonate mixtures of different concentrations can produce a wide range of pH levels in alkaline solutions.

5. Archaeologists matched the goatskins to goat skeletons found on the outskirts of Assur on the banks of the Tigris River.

Could this be real GMAT question? Have 2 answers C and E short-listed. Neither is convincing.
Please help.

siddhu161 wrote:In the ruins of the city-state of Assur, in Ancient Assyria, archaeologists found dried goatskin dating back 3800 years. Analysis of the goatskins showed that they had an unusual pH level that was no lower than that of the calcium carbonate mixture produced by grinding cowrie shells, the most common seashells found on the shore of the Tigris river that runs through Assur. Some believe that this is evidence the Assyrians engaged in the practice of "liming" animal skins: soaking them in alkaline solutions made from crushed seashells in order to create parchment that could be traded with nearby civilizations.

Which of the following, if true, would, together with the information above, provide the best evidence for the claim that the dried goatskins are evidence that the Assyrians engaged in the practice of "liming" animal skins?

1. The calcium carbonate from the cowrie shell is the most common chemical used in modern-day "liming" of parchment and leather.

2. Apart from the Assur discovery, there is reliable evidence that some ancient civilizations, such as the Babylonians, practiced "liming."

3. The goatskins were found in huts that contained equipment known to have been used by Assyrian tradesmen and chemists.

4. Calcium carbonate mixtures of different concentrations can produce a wide range of pH levels in alkaline solutions.

5. Archaeologists matched the goatskins to goat skeletons found on the outskirts of Assur on the banks of the Tigris River.

Could this be real GMAT question? Have 2 answers C and E short-listed. Neither is convincing.
Please help.

Premise: The ph of GOATSKINS found in Assur is no lower than that of ground seashells.
Conclusion: By soaking the goatskins in ALKALINE SOLUTIONS made from ground seashells, Assyrians PRODUCED PAPER that could be TRADED with nearby civilizations.

The correct answer choice must strengthen the assumption that the GOATSKINS found in Assur are linked to ALKALINE SOLUTIONS, PAPER PRODUCTION, and TRADE.

Answer choice C: The goatskins were found in huts that contained equipment known to have been used by Assyrian tradesmen and chemists.
This answer choice supports the assumption that the goatskins are linked to TRADE and to ALKALINE SOLUTIONS.

The correct answer is C.

Answer choice E: Archaeologists matched the goatskins to goat skeletons found on the outskirts of Assur on the banks of the Tigris River.
This answer choice strengthens the PREMISE that the goatskins were found in Assur.
A premise is a FACT not in dispute; it does not need to be strengthened.
Eliminate E.
The correct answer choice must strengthen the LINK between the premise and the conclusion.