Final answer:
Among the given options, the Spinocerebellar pathway does not involve third-order neurons synapsing in the thalamus, which distinguishes it from the dorsal column-medial lemniscus pathway and the spinothalamic tract that do involve such synapses.
Step-by-step explanation:
All of the following pathways require third-order neurons synapsing in the thalamus except: c) Spinocerebellar pathway.
The dorsal column-medial lemniscus pathway and the spinothalamic tract are major sensory pathways that convey information to the brain and involve a series of three neurons, with the third-order neurons synapsing in the thalamus. The spinocerebellar tract, however, does not have its third-order neurons synapsing in the thalamus, making it the correct answer to this question.
The corticospinal pathway, which is primarily involved in motor control rather than sensory processing, is also not characterized by third-order neurons synapsing in the thalamus. However, that option is not listed in the question's choices.