Which of the options is true pertaining to the following statements with respect to the Buddhist Stupas?

i. One of the best examples of the structure of a stupa in the third century BCE is at Bairat in Rajasthan. It is a very grand stupa having a circular mound with a circumambulatory path.

ii. The great stupa at Sanchi was built with bricks during the time of Ashoka, and later, it was covered with stone and many new additions were made.