问题如下图：
选项：
A. 
B. 
C. 
解释：
请问这道题为啥不选A?另外选项C是啥意思？谢谢
NO.PZ2016010802000050 问题如下 A firm thincreases its quantity procewithout any change in per-unit cost is experiencing: A.economies of scale. B.seconomies of scale. C.constant returns to scale. is correct.Output increases in the same proportion input increases occur constant returns to scale.考点规模报酬不变解析题中所属商量增加的同时，单位成本不变，那就是表明规模报酬不变。所以选C如果是增加产量同时单位成本减少，那才是规模经济。 RT
NO.PZ2016010802000050 问题如下 A firm thincreases its quantity procewithout any change in per-unit cost is experiencing: A.economies of scale. B.seconomies of scale. C.constant returns to scale. is correct.Output increases in the same proportion input increases occur constant returns to scale.考点规模报酬不变解析题中所属商量增加的同时，单位成本不变，那就是表明规模报酬不变。所以选C如果是增加产量同时单位成本减少，那才是规模经济。 如题
NO.PZ2016010802000050 seconomies of scale. constant returns to scale. C is correct. Output increases in the same proportion input increases occur constant returns to scale. 考点规模报酬不变 解析题中所属商量增加的同时，单位成本不变，那就是表明规模报酬不变。所以选C 如果是增加产量同时单位成本减少，那才是规模经济。 Constant returns to scale可以详细讲解一下吗？
NO.PZ2016010802000050 seconomies of scale. constant returns to scale. C is correct. Output increases in the same proportion input increases occur constant returns to scale. 考点规模报酬不变 解析题中所属商量增加的同时，单位成本不变，那就是表明规模报酬不变。所以选C 如果是增加产量同时单位成本减少，那才是规模经济。规模报酬在讲义哪里有？老师也没讲这个知识点
NO.PZ2016010802000050 b为何不正确呢，产量增加，价格未变，说明总成本增加，这种情况是规模不经济呀。
