A sudden increase in the production of elephant ivory artifacts on the

Question

A sudden increase in the production of elephant ivory artifacts on the Mediterranean coast of North Africa occurred in the tenth century. Historians explain this increase as the result of an area opening up as a new source of ivory and argue on this basis that the important medieval trade between North Africa and East Africa began at this period.

Each of following, if true, provides some support for the historians’ account described above EXCEPT:

(A) In East Africa gold coins from Mediterranean North Africa have been found at a tenth-century site but at no earlier sites.

(B) The many surviving letters of pre-tenth-century North African merchants include no mention of business transactions involving East Africa.

(C) Excavations in East Africa reveal a tenth-century change in architectural style to reflect North African patterns.

(D) Documents from Mediterranean Europe and North Africa that date back earlier than the tenth century show knowledge of East African animals.

(E) East African carvings in a style characteristic of the tenth century depict seagoing vessels very different from those used by local sailors but of a type common in the Mediterranean.

Minheequang · Accepted Answer

IMO  D . The argument:  East African & North African (near Mediteranean coast) began trading to each other no earlier than 10 century

A sudden increase in the production of elephant ivory artifacts on the Mediterranean
coast of North Africa occurred in the tenth century. Historians explain this increase as
the result of an area opening up as a new source of ivory and argue on this basis that the
important medieval trade between North Africa and East Africa began at this period.
Each of following, if true, provides some support for the historians’ account described
above EXCEPT:
A. In East Africa gold coins from Mediterranean North Africa have been found at a
tenth-century site but at no earlier sites --> gold coins mean business, so this strengthens that their business - East & North Africa near Mediteranean, began no earlier than 10-century 
B. The many surviving letters of pre-tenth-century North African merchants include
no mention of business transactions involving East Africa -->  this eliminates any possibility that North & East have trading to each other earlier than 10 century, thus strengthening the argument 
C. Excavations in East Africa reveal a tenth-century change in architectural style to
reflect North African patterns --> strengthen. From 10 century, East African has been influenced by North African's architecture. This means they began a relation at 10 century, and it was likely business relation 
D. Documents from Mediterranean Europe and North Africa that date back earlier
than the tenth century show knowledge of East African animals --> this mentions about pre 10 century but shows no relations between North African Mediteranean coast & East Africa. It neither strengthens nor weakens, thus the best 
E. East African carvings in a style characteristic of the tenth century depict seagoing
vessels very different from those used by local sailors but of a type common in
the Mediterranean -->  strengthen. At 10 century, East African had seagoing evidences related to that of Mediteranean coast, and because those can be of the Mediteranean coast of North African, so it connects East African & North African mediteranean coast

demeuse81 · Answer

Solution is D

Using the CR bible approach:

Question is of Family #2 -> help
Question type is StrengthenX (the correct answer does not strengthen/support the argument). The correct answer is either neutral or weakens the argument.

All answers but D either strengthen or support the argument. D is neutral. Hence, D is correct.

manav10572 · Answer

A sudden increase in the production of elephant ivory artifacts on the Mediterranean coast of North Africa occurred in the tenth century. Historians explain this increase as the result of an area opening up as a new source of ivory and argue on this basis that the important medieval trade between North Africa and East Africa began at this period. 
Each of following, if true, provides some support for the historians’ account described
above EXCEPT:
A. In East Africa gold coins from Mediterranean North Africa have been found at a tenthcentury site but at no earlier sites.
B. The many surviving letters of pre-tenth-century North African merchants include no mention of business transactions involving East Africa.
C. Excavations in East Africa reveal a tenth-century change in architectural style to reflect North African patterns.
D. Documents from Mediterranean Europe and North Africa that date back earlier than the tenth century show knowledge of East African animals.
E. East African carvings in a style characteristic of the tenth century depict seagoing vessels very different from those used by local sailors but of a type common in the Mediterranean

The conclusion is: the important medieval trade between North Africa and East Africa began at this period (10th century).  We have to find an option that does not strengthen the conclusion. 
A: Coins from N. Africa have been found at E. African sites dating back to 10th century, but not at sites older than 10th century. (Does strengthen the argument)
B: Surviving letters from pre/ before 10th century make no mention of any trade between North and East Africa. Does strengthen the argument).
C: Excavations in E. Africa changed around 10th century to reflect N. African architecture. Does strengthen.
D: Knowledge of E. African animals (possibly elephants- the source of ivory also) before 10th century. It could mean that N. Africa knew of elephants before 10th century, and the trade in Ivory began before the 10th century. (Weakens the argument)
E: Seems irrelevant as there is no reference to N. Africa.

ChrisLele · Answer

In the answer choices, we are looking for a cultural interchange between the two parts of Africa beginning in the tenth century. The idea is that the two cultures came in contact once the North Africans began trading ivory to the East Africans in the tenth century, but not before.

(A), (B), (C), and (E) all provide evidence that the two cultures began interacting in the 10th century.

(D) CORRECT Here the North Africans only have knowledge of East African animals, say rhinos. That North Africans know about rhinos has nothing to do with whether Africans began trading with East Africans.

Hope that makes sense :-D

him1985 · Answer

Documents from Mediterranean Europe and North Africa that date back earlier than the tenth century show knowledge of East African animals -->this mentions about pre 10 century but shows no relations between North African Mediteranean coast & East Africa. 
D is best choice

FALSEnine9 · Answer

It seems as though none of the options talk about the 'new sources of ivory', so the first half of the argument is redundant?

MartyTargetTestPrep · Answer

The first part of the historians' opinion is definitely not as important for determining which choice is correct as their final conclusion "the important medieval trade between North Africa and East Africa began at this period." All of the choices that provide support for their "account" support that final conclusion.

At the same time, the first part is necessary for their argument to work.

devil.rocx · Answer

Can you please confirm whether my reasoning is correct?

Ivory Artifacts increased in 10th Century.
According to Historians - This happened because of a new source of raw material.
The new source came into being because of the new trade that began at the same time between NA and EA.

MartyTargetTestPrep · Answer

That's pretty close, but I'd adjust the last part to the following:

The coming into being of this new source indicates that new trade began at the same time between NA and EA.

KarishmaB · Answer

Premise: 
In 10th century, NA started using a lot more ivory.

Intermediate Conclusion:  
Historian's Explanation for this: This happened because NA found a new source of ivory.

Conclusion: 
Historian's Claim: So medieval trade between NA and EA must have started in 10th century.

We need the option that DOES NOT support this theory.

(A) In East Africa gold coins from Mediterranean North Africa have been found at a tenth-century site but at no earlier sites.

In EA, coins of NA were found from 10th century onwards. Then it does look like trade began between then in 10th century.

(B) The many surviving letters of pre-tenth-century North African merchants include no mention of business transactions involving East Africa.

Pre-10th century, there are no letters in NA about trade with EA. So looks like trade did not begin before 10th century. Again, supports our theory.

(C) Excavations in East Africa reveal a tenth-century change in architectural style to reflect North African patterns.

In EA, architecture changed in 10th century and reflects NA patterns.

(D) Documents from Mediterranean Europe and North Africa that date back earlier than the tenth century show knowledge of East African animals.

Before 10th century documents from NA show mention of EA animals. This indicates some communication between NA and EA before 10th century. Was there trade at that time between them we cannot say but this option doesn't support our trade theory at all. It may not weaken our theory either but it certainly does not support it.

(E) East African carvings in a style characteristic of the tenth century depict seagoing vessels very different from those used by local sailors but of a type common in the Mediterranean.

In 10th century (suggested) in EA we see carvings showing NA ships. This strengthens that trade happened in 10th century between EA and NA. Supports our theory.

Answer (D)

laborumplaceat · Answer

Because D suggests that people in Mediterranean Europe and North Africa already had knowledge of East Africa before the tenth century, it does not support the claim that the important trade began only in the tenth century.
So, D.

egmat · Answer

Key insight for "BEGAN at time X" questions:

To support "trade BEGAN in the 10th century," you need:
• Evidence trade  existed  in the 10th century ✓
• Evidence trade  did NOT exist before  the 10th century ✓

Both types support the claim!

Why B SUPPORTS: 
B says: No mention of East African trade in  pre-10th-century  letters.
→ No prior trade = trade  started later  = supports "began in 10th century" ✓

Why D does NOT support: 
D says: Documents  BEFORE  the 10th century show knowledge of East African animals.
→ Prior knowledge existed = some contact  already  existed =  undermines  "began in 10th century"

Answer: D

A sudden increase in the production of elephant ivory artifacts on the

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A sudden increase in the production of elephant ivory artifacts on the

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