The correct answer is: D. Neuron
A neuron is the basic structural and functional unit of the nervous system. It is a cell that receives, processes, and transmits information through electrical and chemical signals. Neurons are made up of a cell body, dendrites, and an axon. The cell body contains the nucleus and other organelles that are necessary for cell function. The dendrites are short, branched projections that receive signals from other neurons. The axon is a long, slender projection that transmits signals to other neurons.
Centron is a term that is sometimes used to refer to the nucleus of a neuron. However, this term is not commonly used in neuroscience.
Dendron is a term that is used to refer to the short, branched projections of a neuron. Dendrites receive signals from other neurons.
Axon is a term that is used to refer to the long, slender projection of a neuron. Axons transmit signals to other neurons.
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