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
Probe used in western blot: 
Select and explain. 
A. Antibody, B. M-RNA, C. DNA, D. t-RNA
A: Antibody
Answer: A: Antibody 
Explanation: A i.e. Antibody Western blot (immuno blot) analyses protein by antibody labeled probeQ. Nohern blot analyses m-RNA by a radioactive probe and southern blot analysis DNA by radioactive probe.