The given polynomial:
6x+x^2-x^4+3
is a polynomial of degree 4, thus the standard form will be:
ax^4+bx^3+cx^2+dx+e
where
a,b,c,d,e are constants
rewriting our polynomial we shall have:
-x^4+0x^3+x^2+6x+3
this will be simplified to:
-x^4+x^2+6x+3
The answer is:
A] -x^4+x^2+6x+3