Answer:
d. dendrites; axon
Step-by-step explanation:
The structure of a neuron contains the stem-like structure at one end, the cell body contains the nucleus and the long tube-like structure covered with a myelin sheath called axons.
The axons carry the signal away from the cell body in sensory neurons and the dendrites carry the information towards the cell body.
The signals are transmitted in the form of electrical signals which gets converted into the chemical signal at the synaptic junction through the neurotransmitters released by the synaptic knobs.
Thus, Option-D is the correct answer.