This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
C/F of lateral medullary syndrome -a) Ipsilateral numbness of arm, trunkb) Ipsilateral 12th nerve palsyc) Ipsilateral Horner's syndromed) Contralateral pyramidal tract sign. 
Select and explain. 
A. ac, B. ad, C. bc, D. cd
A: ac
Answer: A: ac 
Explanation: None