When marble is flicked off the edge of a table then the at the instant it will move off the table the velocity is horizontal while due to force of gravitation the marble will start accelerating downwards.
So here we will say that the velocity of marble will remain constant through out the motion in X direction as there is no force in that direction
While in Y direction the marble will have gravitational force due to which marble will accelerate downwards
So the path of the marble will be parabolic path
hence the correct answer will be
A.
Only one continuous force is acting on the marble.