________I admit the boy has a gift for music,I don't think he will make a good singer.
A:Since
B:While
C:Until
D:Unless
G20峰会期间,有文章以此为标题:从“APEC蓝”到“西湖蓝”,何时迎来中国蓝?人们关注的是中国的( )
下列四个字母中,既是轴对称图形,又是中心对称图形的是( )