After a 24 hour fast, which of the following is the major metabolic pathway providing oxidizable substrate for skeletal muscle?

A. Lipolysis

B. Gluconeogensis

C. Ketone body synthesis

D. Glycogenolysis

Option C, Ketone body synthesis

Explanation:

Ketone bodies are used as a source of energy when glucose is not easily available as energy source. This usually happens when a person is fasting and hence does not intake any glucose. There are three main ketone bodies a) acetoacetate, b) 3-beta-hydroxybutyrate and c) acetone. When our body do not receive food for a long time or a person undergo rigorous and continuous physical exercise, then the level of ketone bodies increases in the blood

Hence, option C is correct

Answer: I believe the answer would be A. If it is wrong sorry.