Flexible budget Vs Fixed budget

Which TWO of the following statements explain why a flexible budget can be more useful in control than a fixed budget?
1.The budget is designed to change as activity levels change
2.Direct cost variances are more meaningful
3.Action can be taken to improve adverse variances
4.The budget gives the actual level of activity

Hello, I am confused with this question.
I chose 1&4. However the answer is 2&3
Could anyone please help?
Thank you in advance.