If a bar magnet is falling through a loop of wire, the induced current in the loop of wire sets up a field which exerts a force on the magnet. This force between the magnet and the loop will be attractive when:

When the magnet is leaving the loop

Explanation:

According to Lenz's law the direction of an induced current in a conductor will oppose the effect which produces it. As the current is induced in the wire loop and force is exerted on the magnet, the force between the magnet and the loop will be attractive when the magnet is leaving the loop because it's is the one that produces the effect which create the current.

photocells convert light energy to electricity

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.