题目

阅读短文，从每题所给的A、B、C和D四个选项中，选出最佳选项。Nola is a 41-year-old northern white rhino (犀牛) that lives at the SanDiego Zoo Safari Park in Escondido, California. She is one of only four remainingnorthern white rhinos in the world, and the only one in the western part of theearth. The other three live in Kenya (肯尼亚).Rhinos have lived on earth for more than 40 million years, but they are nowat the risk of dying out. Hunters illegally hunt rhinos for their horns (角), which are used for art,jewelry, and decorations. They sell the horns for thousa泪液有杀菌作用，其原因是A.泪液中含有抗菌素B.泪液中含有溶菌酶C.泪液中含有抗体D.泪液中含吞噬细胞