It is assumed that Laozi must have lived （）two historical periods in Chinese history known as Spring and Autumn Period and the Warring States Period. (time: 2:44)

It is assumed that Laozi must have lived （）two historical periods in Chinese history known as Spring and Autumn Period and the Warring States Period. (time: 2:44)
A.at the junction of
B.in the connection
C.on the adjunction of
D.conjunction
正确答案：at the junction of