With regards to what is expected when referencing an object's properties made through the use of the Circle constructor, does the "this" reference need to be included within the method for each property?

```
// option A
function Circle (radius) {
this.radius = radius;
this.area = function () {
return Math.PI * this.radius * this.radius;
};
this.perimeter = function () {
return 2 * Math.PI * this.radius;
};
};
// option B
function Circle (radius) {
this.radius = radius;
this.area = function () {
return Math.PI * radius * radius;
};
this.perimeter = function () {
return 2 * Math.PI * radius;
};
};
```