Which of These Actions Does the Brain Do During Fasting

Which of these actions does the brain do during fasting or starvation?

A) It converts endogenous fatty acids into β-hydroxybutyrate.
B) It utilizes β-hydroxybutyrate from the blood stream.
C) It utilizes amino acids for fuel from degradation of brain protein.
D) It utilizes its glycogen stores as a first responding source of fuel.