求解 Tpo 12中的阅读题

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请大家帮忙看下 这道TPO 12 里面 的第一篇  11题
Paragraph 6：Occasionally one can determine whether stone tools were used in the right hand or the left, and it is even possible to assess how far back this feature can be traced. In stone toolmaking experiments, Nick Toth, a right-hander, held the core (the stone that would become the tool) in his left hand and the hammer stone in his right. As the tool was made, the core was rotated clockwise, and the flakes, removed in sequence, had a little crescent of cortex (the core's outer surface) on the side. Toth's knapping produced 56 percent flakes with the cortex on the right, and 44 percent left-oriented flakes. A left-handed toolmaker would produce the opposite pattern Toth has applied these criteria to the similarly made pebble tools from a number of early sites (before 1.5 million years) at Koobi For a, Kenya, probably made by Homo habilis. At seven sites he found that 57 percent of the flakes were right-oriented, and 43 percent left, a pattern almost identical to that produced today.

11. What was the purpose of Toth's tool making experiment described in paragraph 6?
○ To shape tools that could be used by either hand
○ To produce replicas of early tools for display in museums
○ To imitate the production of pebble tools from early sites
○ To determine which handmade the early tools

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