Recognizing most affecting factors on respose/output?

Hi Matlabers,

I have some variables like A,B,C,D.

A,B and C are independant parameters and D is respose of A, B and C togther with some non-linear relationship.

How can I know whoch parameter out of A,B and C affecting D in more extent ?

It will be better if I get weightage factors for these three independant parameters/variables

Thanks in advance !