Which of the Following Accurately Describes the Origins of the Kshatriya

Which of the following accurately describes the origins of the Kshatriya caste?

A) They were descended from agricultural commoners,the original residents of South Asia.
B) They were descended from the most politically powerful clans that entered South Asia,and became rulers of the new land.
C) They were descended from servants and menial laborers,and became the lowest caste.
D) They were descended from Vedic priests and became the highest caste in South Asia.