Which of the following statements are correct？

Which of the following statements are correct？
A.Ethics are a set of moral principles that guide attitudes and behaviour.
B.Ethics are a set of rules.
C.Ethics are subjective and imprecise.
D.Ethics depend on social， cultural and individual factors.
正确答案：Ethics are a set of moral principles that guide attitudes and behaviour.Ethics are subjective and imprecise.Ethics depend on social， cultural and individual factors.