41. 下列何種藥物最適合用於恆齒之根尖成形術(apexification)?(A) 蟻醛甲酚合劑(formocresol)(B) 氫氧化鈣(calcium hydroxide)(C) 戊二醛(glutaraldehyde)(D) 硫化鐵(ferric sulfate)