单项选择题
JavaScript代码如下所示,请问代码最后的输出结果是var person = { firstName: "John", lastName : "Doe", fullName : function() { return this.firstName + " " + this.lastName; }};document.write( person.fullName);( )。
A.John
B.Doe
C.John Doe
D.function() { return this.firstName + " " + this.lastName; }