Alright. So this one's asking us which of the following statements about pathways of sympathetic innervation is false. So, we're going to, kind of, run through these and draw them as we go just to, kind of, help us visualize it. We're going to draw a spinal cord over here. We'll draw our sympathetic trunk with our ganglia over here. This is not going to be anatomically accurate. I'm just going to kind of visualize what we're talking about. And I'll draw a collateral ganglion over there as well in case we need it later. Alright. So option A reads, a preganglionic and postganglionic neuron can synapse in a trunk ganglion at the same level. So that would look like this: we'd have our impulse happen in that spinal cord, preganglionic fiber going to the same level of the sympathetic trunk, and then a synapse happening right there at that same level. And that's totally possible. Right? So, A is true and A can stay.
Option B reads, a preganglionic and postganglionic neuron can synapse in a trunk ganglion at a higher level. So that would look like this: we have our impulse start in the spinal cord, our preganglionic fiber going to the sympathetic trunk and then traveling up to a higher ganglia. It could also go lower. Right? And then synapsing and then that postganglionic fiber would extend out and that is also possible. So B is true. B can stay.
Option C reads, a preganglionic and postganglionic neuron can synapse in the ventral horn of the spinal cord, and that one's not looking so good. Right? Just think about how these fibers are named. Right? Preganglionic and postganglionic. For them to synapse in the spinal cord, they would both have to exist over here in that preganglionic space. So that doesn't make any sense. So our answer is indeed going to be C. C is false. That cannot happen.
Just to kind of finish out the example here, option D reads a preganglionic and postganglionic neuron can synapse in a collateral ganglion, and that can also happen. Right? So our impulse would start in the spinal cord, that preganglionic fiber would travel through the sympathetic trunk to a collateral ganglia and our synapse would take place there. Right? So our answer here is going to be C is false. These neurons cannot synapse in the spinal cord. And there you go.