A concave spherical mirror has a focal length of 12 cm. If an erect object is placed 6 cm in front of it: A. the magnification is 2 and the image is erect B. the magnification is 2 and the image is inverted C. the magnification is 0.67 and the image is erect D. the magnification is 0.67 and the image is inverted E. the magnification is 0.5 and the image is erect