题干
—What shall we do tomorrow?
—Tomorrow we will go on a trip to Guangzhou．
A：fly
B：open up
C：make a journey
答案(点此获取答案解析）
C
—What shall we do tomorrow?
—Tomorrow we will go on a trip to Guangzhou．
A：fly
B：open up
C：make a journey
，则实数a取值范围是（ ）