Which of the following features are correct? Choose correct option. a. Erythropoietin is a peptide hormone produced by the juxtaglomerular cells of the kidney. b. Erythropoietin stimulates erythropoiesis (formation of RBCs). c. Gastrin acts on the gastric glands and stimulates the secretion of HCl and pepsinogen. d. Secretin acts on the exocrine pancreas and stimulates secretion of water and bicarbonate ions.