单项选择题

有如下程序:
#include ＜iostream＞
using namespace std;
class BASE
public:
～BASE() cout＜＜"BASE";
;
class DERIVED: public BASE
public:
～DERIVED() cout＜；"DERIVED";
;
int main()DERIVED x; return 0;
执行后的输出结果是______ 。