为了让Dog类的构造函数能正确地调用其父类Animal的构造⽅法，横线线处应填入（    ）。

class Animal{
public:
	std::string name;

	Animal(std::string str):name(str){
			std::cout<<"Animal created\n";
		}
	virtual void speak(){
		cout<<"Animal speaks"<< endl;
	}
};

class Dog :public Animal{
	std::string breed;
public:
	Dog(std::string name, std::string b) ：_______________,breed(b){
			std::cout<< "Dog created\n";
		}
	void speak()override {
		cout<<"Dog barks"<< endl;
	}
};

int main(){
	Animal* p= new Dog("Rex","Labrador");
	p->speak();
	delete p;
	return 0;
}