题目

Florida is celebrating a big anniversary this year. Five hundred years ago, on April 2, 1513, Spanish explorer Juan Ponce arrived on the east coast of what is now Florida. Native Americans had been living there for centuries, but Ponce was the first European to set foot in what would become the United States. According to legend, Ponce may have landed in Florida by mistake. He is said to have been looking for an island called Bimini and its Fountain(喷泉) of Youth. The magical fountain could supposedly make old people young again. Instead, Ponce landed on Florida and claimed it for S乙酸和乙醇反应生成乙酸乙酯，羧酸与醇反应生成酯的反应称为酯化反应。若乙酸中氧是普通氧，乙醇中氧是18O，乙酸和乙醇在浓硫酸催化作用下反应后的物质中含有18O共有（ ）种A.1种B.2种C.3种D.4种