The gravitational potential changes uniformly from $-20Jk{g}^{-1}$ to $-40Jk{g}^{-1}$ as one moves along x-axis from $x=-1\text{m}$ to $x=+1\text{m}.$ Then select the correct statement(s) about gravitational field intensity at origin

The gravitational field intensity at $x=0$  must be equal to $10Nk{g}^{-1}$

The gravitational field intensity at $x=0$  may be equal to $10Nk{g}^{-1}$

The gravitational field intensity at $x=0$  may be greater than $10Nk{g}^{-1}$

The gravitational field intensity at $x=0$  must be less than $10Nk{g}^{-1}$