D

To determine the motion of the charge +q thrown toward the disc, we can analyze the effects of electrostatic forces involved.
Step 1: Recognize that the disc has a uniform surface charge density. The total charge on this disc will create an electric field, E, in the space around it.
Step 2: The charge +q will experience an electrostatic force due to the electric field created by the disc as it approaches. The direction of the force will depend on the sign of the charge and the nature of the electric field.
Step 3: Depending on the magnitude of the electric field E at the position of charge +q when it reaches the disc, three scenarios can occur:

• If the kinetic energy of +q is sufficient to overcome the electric potential energy (due to the electric field), it may hit the disc at the center and pass through.
• If the electric field is strong enough, it may decelerate +q, causing it to return back along its path after touching the disc.
• Alternatively, if the electric field is sufficiently strong, the charge may return back along its path without actually making contact with the disc.

Conclusion: Hence, depending on the magnitude of E and the initial kinetic energy of the charge +q, any of the aforementioned scenarios is possible. Therefore, the correct answer is D.