As the bird releases the drop there is no internal force which will drive it into circular path but it will fall on tangent of the arc at the point of release because it has a tangential velocity same as bird. Path will be parabola in vertical plane.
As the person is on circular arc constantly moving it will never meet that drop.
A.Positive as work=force×distance (assuming that distance is always a constant) the work will always be positive as the force is always positive(this is because force=mass×acceleration where the acceleration is always positive unless the mass is being slowed down)
