Answer:
4. Parabola
Step-by-step explanation:
The motion of the flight of the grenade is a projectile motion, it's shape is best illustrated using a parabolic diagram.
It's not a circle as the path is not totally round.
It's not an ellipse as the path of motion is not a a completely bounded shape.
Its not a hyperbola as a hyperbola is an open curve with two branches.
Its a parabolic shape because a parabola has just one branch