I'm saying A but I might be wrong that's what I think I tried my best
Real Depth is actual distance of an object beneath the surface, as would be measured by submerging a perfect ruler along with it. Apparent depth in a medium is the depth of an object in a denser medium as seen from the rarer medium. Its value is smaller than the real depth.
The answer would be letter A. globular cluster. This group of very old stars that are clustered together in a spherical in shape and can contain from 10,000 to several million is called a globular cluster. In our galaxy, there are 150 globular clusters.
Radiation. Have a nice day.
