Which of the following statements about retinal neurons is correct? 关于视网膜神经元，下列哪项陈述是正确的？单项选择题

Some retinal ganglion cells are “on centre” (responding to light in the middle their receptive field), others are “off centre” (inhibited by light in the centre of their receptive field). 有些视网膜神经节细胞是“中心激活型”（对感受野中心的光线有反应），另一些则是“中心抑制型”（对感受野中心的光线有抑制作用）。

Some bipolar cells (the “on bipolars”) generate action potentials, whereas other types of bipolar cells (“off biploars”) only generate graded hyperpolarisations. 有些双极细胞（“开启型双极细胞”）产生动作电位，而其他类型的双极细胞（“关闭型双极细胞”）只产生分级超极化。

There are many types of bipolar cell that receive input from rod photoreceptors, but only one type of bipolar cell receives input from cone photoreceptors. 有许多类型的双极细胞可以接收来自视杆感光细胞的输入，但只有一种类型的双极细胞可以接收来自视锥感光细胞的输入。

Some horizontal cells are excitatory (using glutamate as their transmitter), other horizontal cells are inhibitory (using GABA as their transmitter). 有些水平细胞是兴奋性的（以谷氨酸为神经递质），另一些水平细胞是抑制性的（以 GABA 为神经递质）。