Which statement is FALSE regarding regulation of the pyruvate dehydrogenase complex?
A) In E. coli, a high ratio of [NAD+]/[NADH] activates the complex.
B) In E. coli, high levels of ATP enhance the activity of pyruvate dehydrogenase kinase.
C) In plants, NH4+ inhibits the complex by enhancing the activity of pyruvate dehydrogenase kinase.
D) In mammals, both fatty acids and acetyl-CoA inhibit the complex.
E) In skeletal muscle, both NAD+ and Ca2+ activate the complex.
The answer is B.
Is there a hint of why C is correct? Thanks