下列地理现象主要由地球公转产生的是（　　）

A．太阳的东升西落

B．春、夏、秋、冬的变化和更替

C．昼夜更替

D．海陆变迁

I might fail, but _____ I insist on doing it. I don't mind it. [ ]

A. however

B. anyhow

C. yet

D. meanwhile