1.The football team has done well this year._____have traine

1.The football team has done well this year._____have trained very hard.
A.All players B.All their players
C.All its players D.All of players
为什么C是对的,其它都是错的
2.Radio ________in our life
A.is used widely
B.is widely used
为什么是B而不是A啊
副词什么时候放在前面,什么时候放在后面啊