A light signal with no level crossing sign is positioned before a level crossing, and in front of a junction with a road to the right. The red light is illuminated. Where must you wait?

You answered correctly. When a red light signal is shown before a level crossing, you must stop and wait at the stop line if one is present. If there is no stop line, you must stop in front of the light signal itself. These rules exist to ensure you stop at a safe distance from the level crossing, protecting you and other road users from approaching trains. You must never continue driving up to the crossing when the red light is on. Always wait until the signal changes and it is safe to proceed.