维生素E在国外被美称为“生命奇迹丸”，是一种脂溶性维生素，对

维生素E在国外被美称为“生命奇迹丸”，是一种脂溶性维生素，对抗衰老等有特殊作用，经研究发现维生素E有α、β、γ、δ四种类型，其结构简式如下：

其中R为-CH₂CH₂CH₂[CH(CH₃)CH₂CH₂]₂CH(CH₃)₂，上述互为同分异构体的是（）

A．α β B．β γ C．γδ D．α δ

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