The diagram below shows three different types of neurones, labelled P, Q, and R, which are involved in nervous coordination.
Which of the following statements correctly identifies the types of neurones and their functional or structural features?
P\text{P}P has its cell body located in the grey matter of the spinal cord, and Q\text{Q}Q is heavily myelinated to speed up transmission.
Q\text{Q}Q is a sensory neurone that connects directly to receptor cells, and R\text{R}R transmits impulses from the central nervous system to P\text{P}P.
P\text{P}P transmits impulses from sensory receptors towards the central nervous system, and R\text{R}R is a myelinated neurone that transmits impulses to effectors.
P\text{P}P is a motor neurone with its cell body in the dorsal root ganglion, and R\text{R}R is a sensory neurone with dendrites that receive impulses from relay neurones.