Explain the relationship between these terms : raj and "jewel in the crown"

The correct answer to this open question is the following.

Great Britain had many colonies around the world. In Africa, its presence was more than notable during the "Scramble for Africa." However, Britain also had colonies in Asia. Indian, being the "jewel of the crown." A name it received for the many raw materials and natural resources that were exploited bu the British. The term "Raj" can be identified as the presence of the British government in India. It started in 1858 and ended until 1947. The English monarchy directly ruled India after the Indian Rebellion of 1957. That is when Queen Victoria ordered that India must be ruled by the crown of England.

an ethnic enclave is a geographic area with high ethnic concentration,

i dont know. sorry : (