— Hello, may I speak to your father, please?
— Sorry, my father _________ to Shanghai. He went there this morning.
A:goes
B:has gone
C:have been
D:go
由于转β-胡萝卜素基因的水稻产生的米粒富含β-胡萝卜素,被称为“金色大米”。这种“金色大米”形成过程不需要的酶是 ( )
图①~④中,正确反映河流枯水期水体补给关系的是( )