The sum of order and degree of differential equation $1+{\left(\frac{\mathrm{dy}}{\mathrm{dx}}\right)}^4=7{\left(\frac{{\mathrm{d}}^2\mathrm{y}}{{\mathrm{dx}}^2}\right)}^3 \mathrm{is}$

$\left(\mathrm{c}\right) \mathrm{Given}, \mathrm{differential} \mathrm{equation} \mathrm{is} 1+{\left(\frac{\mathrm{dy}}{\mathrm{dx}}\right)}^4=7{\left(\frac{{\mathrm{d}}^2\mathrm{y}}{{\mathrm{dx}}^2}\right)}^3.$
Here, highest order derivative is $\frac{{\mathrm{d}}^2\mathrm{y}}{{\mathrm{dx}}^2},$, whose highest power is 3 .
So, order =2 and degree =3
Sum of order and degree =2+3=5