The key word is TERMINATE, meaning they are looking for where the first order neuron ends. Answers A/B would apply if it was pain and temperature involved, as the first order neuron of the Spinothalamic tract terminates in the spinal cord and crosses there. For DCML, the first order neuron terminates on the opposite side in the medulla, so a R lesion would terminate on the L side of the medulla. The question is essentially a long winded way to ask ‘where does the first order neuron of the DCML terminate?’
