According to the equation, the sign of x^2 is positive, so the curve should be a ‘smile’ shape, so A should be excluded.
Also, x^2-4=0
(x-2)(x+2)=0
x= 2 or -2
means that the curve should cut x-axis at point (-2,0) &(2,0), the best represented graph should be Option C
Hope this can help.
