有如下类声明: class TestClass int x; public: TestClass (int n) x=n; ; class TestClass 1 :public TestClass int y; public: TestClass 1 (int a,int b); 在构造函数TestClass1的下列定义中,正确的是( )。
A) TestClass1::YestClassl (int a,int b):x(a),y(b)
B) TestClass 1 ::TestClass 1 (int a,int b):TestClass(a),y(b)
C ) YestClass 1 ::TestClass 1 (int a,int b):x(a),TestClass 1(b)
D) TestClass 1 ::TestClass 1 (int a,int b):TestClass(a),TestClass 1 (b)