The Surface of the Sun near Its Edge Appears Dimmer

The surface of the Sun near its edge appears dimmer and cooler than at the center of the disk when viewed in visible light because we see:

A) deeper into the Sun near the edge than at disk center and temperature increases with depth.
B) light from the edge that has had to pass through more of the absorbing chromosphere and corona and is thereby reduced in intensity.
C) less deeply into the Sun near the edge than at disk center and temperature decreases with depth.
D) less deeply into the Sun near the edge than at disk center and temperature increases with depth.