Which endocrine gland is called 'the Throne of immunity'?

According to the modern theory of aging,our body gradually loses its ability to resist bacteria and pathogens. This process is caused by the gradual disappearance (atrophy) of which organ?

Which of the following glands is responsible for immunity in humans?

Where are Hassall's corpuscles found?

Old people have a weak immune system. What could be the reason?

Which one of the following four glands is correctly matched with the accompanying description?