The correct sequence starts with the doctor (3), followed by the treatment (2), then the bill (1), followed by the diagnosis (4), and finally the patient (5).
Therefore, the correct sequence is (3), (2), (1), (4), (5).
Hence, the correct answer is (C).
Which of the following is correct? 
Look at this series:
U32, V29, ____, X23, Y20, ....
What number should fill the blank?
CUBAEDEDABEBBAUCDBCADB