which function is called

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which function is called

when a derived object calls the base class member function, inside which calls another virtual member function, which is implemented inside the derived class, so which virtual member function is actually called ? 

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#include <iostream>
class Weld {
	public: 
		Weld(){};
		virtual ~Weld(){};
		virtual bool getDataIndex(){
			std::cout << "Weld::getDataIndex" << std::endl;
			return true ; 
		}
		bool getInternalDataList(){	
			return getDataIndex();
		}
};
class SpotWeld: public Weld{
	public:
		SpotWeld(){};
		virtual ~SpotWeld(){};
		virtual bool getDataIndex(){
			std::cout << "SpotWeld::getDataIndex" << std::endl;
			return true; 
		}
};
class ACM2 : public SpotWeld{
	public:
		ACM2(){};
		~ACM2(){};
		virtual bool getDataIndex(){
			std::cout << "ACM2::getDataIndex" << std::endl;
			return true;
		}
		bool getPoints(){
			return getInternalDataList();
		}
};
int main(){
	ACM2  acm2 ;
	acm2.getPoints();
	return 0;
}

output is:

ACM2::getDataIndex

so the derived object always calls the member function that most closest to its own class domain first, even if this member function is called from a base class member function.