Both the earth and the moon are subject to gravitational force of the sun. As observed from the sun, the orbit of the moon:
   
1. will be elliptical.
2. will not be strictly elliptical because the total gravitational force on it is not central.
3. is not elliptical but will necessarily be a closed curve.
4. deviates considerably from being elliptical due to the influence of planets other than the earth.
Hint: The motion of a body depends on the forces acting on it.
Step: Observe the forces acting on the moon.
As observed from the sun, two types of forces are acting on the moon, one is due to the gravitational attraction between the sun and the moon and the other is due to gravitational attraction between the earth and the moon. Hence, the total force on the moon is not central.