Graph is attached.!

the graph shows the path of light from a wall reflecting off mirrored ceiling tiles, where x is the distance from the wall in feet and y is height in feet along the wall where the light source hangs.

which statement describes the room based on the graph?

a.) the ceiling is 10 feet high.
b.) the ceiling is 20 feet high.
c.) the light source is 10 feet off the ground.
d.) the light source is 20 feet off the ground.