Primary sensory afferents never cross the midline:
a. true
b. false

The correct answer is option A- true.

Explanation:

Primary sensory afferentS are a part of the somatosensory neuron pathway which transmits the neurons from the stimulus to the CNS. These neurons are divided into three types: primary, secondary and tertiary afferent neurons.

The primary neurons are the neurons which transmit the stimulus generated impulse form the organ to dorsal root ganglion where they transmit the signals to the secondary neurons. These secondary neurons decussate at the midline medulla through medial lemniscus.

Since it is the secondary neurons which decussate at midline, therefore, the option A- true is the correct answer.

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