students 集合中已经存在一条记录 {"_id":"1001","name":"Jack"} ,下面哪句命令可以成功运行?
A.
db.students.insert({"_id":"1001","name":"Rose","age":18})
B.
db.students.insert({"_id":"1001","name":"Tom"})
C.
db.students.save({"_id":"1001","name":"Tom"})
D.
db.students.save({"_id":"1001","name":Tom,年龄:19})