有以下程序: #include<iostream> using namespace std; class sample { private: int n; public: sample(){} sample(int m) { n=m; } sample add(sample s1,sample s2) { this->n=s1.n+S2.n; return(*this); } void disp() { cout<<"n="<<n<<end1; } }; int main() { sample s1(10),s2(5),s3; s3.add(s1,s2); s3.disp(); retyrn 0; } 程序运行后,输出的结果是
A.n=10
B.n=5
C.n=20
D.n=15