Pathogenic means bacterium, virus, or other micro organism that causes disease. So the answer is C.
The mesencephalon gives rise to the midbrain and aqueduct of
the midbrian(cerebal aqueduct). Both the prosencephalon and rhombencephalon
develops in to the metencephalon and myelencephalon. The telencephalon develops into the cerebrum
and lateral ventricles. The diencephalon forms the thalamus, hypothalamus, and
epithalamus.
