"The Signs to Watch for in Acute Diseases Are as Follows

"The signs to watch for in acute diseases are as follows: First, study the patient's face; whether it has a healthy look and in particular whether it is exactly as it normally is. If the patient's normal appearance is preserved, this is best; just as the more abnormal it is, the worse it is.…" What can we conclude about Hippocrates's methods from this passage (Thinking Like a Historian: Hellenistic Medicine) ?

A) That he believed that close observation of patients was important
B) That he believed physicians should study astronomical charts
C) That he believed most diseases could be cured with charms
D) That he believed that patients should be subjected to a variety of medical tests