Given is an OpenGL program with the display method

void display(void)

{

// clear all pixels in frame buffer

glClear(GL_COLOR_BUFFER_BIT);

glColor3f(0.0, 0.0, 0.0);

glBegin(GL_TRIANGLE_FAN);

glVertex2f(300, 100);

glVertex2f(100, 300);

glVertex2f(100, 100);

glVertex2f(200, 0);

glEnd();

glFlush();

What shape does this display method draw?

(d) None of the above