Answer
An ellipsoid of revolution as shown in graph (d).
Work Step by Step
Since, we have $x^2+y^2+4z^2=10$
This can be re-written as:
$\dfrac{x^2}{(\sqrt{10})^2}+\dfrac{y^2}{(\sqrt{10})^2}+\dfrac{z^2}{(\sqrt{10}/2)^2}=1$
Thus, the above equation is a graph for the ellipsoid of revolution as shown in graph (d).
