Refer to the figure shown.
According to the figure, which enzyme(s) is(are) upregulated during the fetal stage of the rat?

A) Glycogen synthetase
B) Phosphoenolpyruvate carboxykinase
C) Glycogen synthetase and phosphoenolpyruvate carboxykinase
D) Glucokinase and phosphoenolpyruvate carboxykinase