选择恰当的应答语( )
A:Here is the chart.
B:My father is a teacher.
C:Sure,please hold on.
— ______ do you get up in the morning?
—At six.
对温室大棚里的农作物,采取适当措施能提高光合作用效率,增加产量,以下措施不能起到这种作用的是( )