In the dark forests _________, some large enough to hold several English towns.

A．stand many lakes

B．lie many lakes

C．many lakes lie

D．many lakes stand

在下面横线上填上适当的语句，完成程序。
#include ＜iostream＞
using namespace std;
class Base

int x;
public:
Base(int i) x=i;
～Base()
;
class Derived: public Base

public:
______∥完成类 Derive 构造函数的定义
;
int main()

Derived Obj;
return 0;

在横线处应填入的语句是 【11】 。