【单选题】查询职称为讲师的姓名,年龄和性别,正确的语句是?
A.db.teachers.aggregate([ {$match:{"prof":"讲师"}}, {$project:{"name":1,"age":1,"sex":1,"_id":0}} ])
B.db.teachers.aggregate([ {$match:{"prof":"讲师"}}, {$project:{"name":1,"age":1,"sex":1}} ])
C.db.teachers.find("prof":"讲师",{"name":1,"age":1,"sex":1})
D.db.teachers.find({"prof":"讲师","name":1,"age":1,"sex":1})