We can feel things are heavy because ______.
A.weight is a fixed quality in an object
B.they are far away from the center of the earth
C.of the earth's strong attraction for them
D.they are not taken away from the surface of the earth
为了保护您的账号安全,请在“上学吧”公众号进行验证,点击“官网服务”-“账号验证”后输入验证码“”完成验证,验证成功后方可继续查看答案!