Stroke characterized by left hemiparesis and right CN12 palsy. Crossed findings mean a brainstem lesion. Right (ipsilateral) tongue, left-sided (contralateral) weakness means the exiting right hypoglossal nerve has been affected (within the right medulla). C is the pyramid where the corticospinal tract runs to control muscles (prior to the decussation). This is known as the medial medullary syndrome or Dejerine syndrome.

if we know that dorsal coloumn ascending is medial and decussate in medulla and ascend contralaterally then we will choose c

rule of 4: (check for Boards and beyond video of rule of 4 on youtube if you haven't watched it already): proprioception is messed up --> medial laminiscus (M is in the middle) tongue movement is messed up --> CN12 --> divides by 12 so its in the middle and also its in the medulla because CN 9,10,11,12 are in the medulla. I thought about vagus at first because they said slurred speech but then they mention tongue deviation so I knew thats CN12 and the reason for slurred speech.