问题：
[单选题]The following statements concern the structure of a synapse:
以下叙述关于突触结构描述正确的是
ASynapses may be axodendritic, axosomatic, or axoaxonic. 突触可以是轴突-树突，轴突-胞体或轴突-轴突突触。
BPostsynaptic membranes and measures about 200nm. 突触间隙是突触前膜和突触后膜之间的间隙，大小约为200nm。
CPresynaptic vesicles do not contain the neurotransmitter substance. 突触前囊泡不包含神经递质。
DAll neurons produce and release several types of transmitter substances at all their nerve endings. 所有神经元在其所有神经末梢均可产生并释放几种类型的递质。
EThe subsynaptic web lies beneath the presynaptic membrane. 突触下纤网位于突触前膜下方。
