When may a tram be overtaken on the left?

You are correct that a tram may be overtaken on the left in two specific situations: in one-way streets and when the tram rails are positioned so far to the right that overtaking on the left is necessary and safe. In German traffic rules, overtaking a tram on the left is generally prohibited unless these conditions apply, because trams have fixed tracks and other traffic must accommodate their movement carefully. The third option is incorrect because blocked lanes to the right do not justify overtaking a tram on the left outside of the specified cases. Remember, always prioritize safety and ensure that overtaking maneuvers follow these rules to avoid accidents or violations.