Ans: A
Explanation: Neurons are the structural and functional units of the nervous tissue. The elongated and slender processes of the neurons are the nerve fibres. Each neuron consists of a cell body or cyton with nucleus and cytoplasm. The dendrons are short and highly branched protoplasmic processes of cyton. The axon is a single, long fibre like process that develops from the cyton and end up with fine terminal branches.