Which best describes the caste system?

Though caste system is only in Hindu society, it has nothing to do with the religion. To understand this, we have to date back to the Vedic Culture, when there was no mention of Hinduism or Hindu. It was a Vedic Culture. Coming back to the "Caste", it was the division of labour. Any country requires four major contributions to progress. Broadly they were identified as: 1. Spirituality, Service, Education etc. (Brahmin caste) 2. A strong and powerful defence to sustain external forces (Kshatriya caste) 3. Strong economy to promote, sustain and progress (Vysya caste) 4. Different services, mostly associated with agricultural and allied activites, which include labour, iron industry, construction industry,metal industry, pottery or any other related field, where labour is involved. (Sudra caste) Accordingly the society was divided, "BASED ON THE WORK THEY PERFORM, AND NOT NOT NOT BY THEIR PARENTAL ORIGIN OF BIRTH". A person was free to choose the caste of his liking, choice and ability. This was a well defined, well structured design of a society, which has served the ancient Vedi Culture for many many thousands of years. However, with the passage of time, this system was misinterpreted and the caste is attributed to birth. There is also a reference in Bhagavat Gita (I am not able to give the exact sloks reference number) where in Bhagavan Krishna says, "I have divided you all into these four categories, based upon the attributes (Gunas) and the work you perform (Karmas you perform)". Nowhere he said that the caste is by birth. It should be looked upon and the Caste System should be revered and respected, that it had served the purpose for thousands of years. But, with the changed circumstances when we have outgrown, we should abondon the caste system.