<prompt> Carbamoyl phosphate intermediates the synthesis ofUreaUrea PyrimidineUric acidKetone body  <response>: B Urea Pyrimidine Biosynthesis of urea begins with the condensation of CC2, NHs and ATP to form carbamoyl phosphate, a reaction catalyzed by carbamoyl phosphate synthase I which is a mitochondrial enzyme, and rate limiting or pacemaker enzyme and the enzyme is active only in the presence of its allosteric activator N-acetylglutamate, which enhances the affinity of synthase for ATP. 