我们吃的豆腐中的营养物质，主要是从大豆种子的哪种结构中提取出来的（ ）
A．胚根
B．胚芽
C．胚乳
D．子叶
大豆属于双子叶植物，其种子的结构包括种皮和胚．种皮起保护作用；胚包括胚根、胚芽、胚轴和子叶，胚根将来发育成根，胚芽将来发育成茎和叶，胚轴将来发育成连接茎和根的部位，子叶肥厚，贮存营养物质．因此，我们吃的豆腐中的营养物质主要从大豆种子的子叶中获取的．
故选：D
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