A. Cell body
B. Axon
C. Dendrites
D. Nerve fibres
参考答案:
A
本题详细解析:
Explanation：
Letter X indicates the cell body, which contains the cytoplasm and the nucleus. Choice A is correct.
An axon is a long, thin projection of a neuron that carries action potentials away from the cell body, Choice B is incorrect. Dendrites are multiple specialised extensions branching from a neuron’s cell body or dendron, responsible for receiving incoming signals from other neurons or sensory receptors, Choice C is incorrect. Nerve fibres are a general term for any long, slender projection from a cell body that is capable of transmitting electrical signals - it can be an axon or dendron, Choice D is incorrect.
