From this sign onwards, which lights must we use?

A)Position lights.
B)Low-beam headlights in any case.
C)Low-beam or high-beam headlights depending on the circumstances.Correct
The sign indicates the obligation for drivers to drive with at least dipped or low-beam headlights, regardless of the visibility or lighting conditions of the road, from the location where the sign is placed until another sign indicating the end of this obligation.
If we are driving on an insufficiently lit interurban road, at more than 40 km/h and without risk of dazzling, we must use high-beam headlights.
Remember that for driving we cannot do so with only the position lights. We must use position lights plus another light.
If we are driving on an insufficiently lit interurban road, at more than 40 km/h and without risk of dazzling, we must use high-beam headlights.
Remember that for driving we cannot do so with only the position lights. We must use position lights plus another light.