Big bowl of tea is one of the characteristic cultures of Han nationality in China. It was popular in old Beijing during the liberation period, so A was excluded. The Dai people take rice as the staple food, pineapple rice is the famous food of the Dai people, and the most distinctive one is bamboo tube rice, so B is correct; Tap dancing is a Tibetan folk song and dance in China. Elephant dance is a traditional dance that spreads in Mengding, Gengma County, Yunnan Province. It is called "Zhang Jia" in Dai language and is a traditional dance of Dai people in Xishuangbanna.

So choose: BD.