You may be very intelligent. You should be careful about what you are going to do.

A. No matter why intelligent you may be, you should be careful about what you are going to do.

B. No matter what intelligent you may be, you should be careful about what you are going to do.

C. No matter how intelligent you may be, you should be careful about what you are going to do.

D. No matter whatever intelligent you may be, you should be careful about what you are going to do.