At what maximum speed are you allowed to drive on the road beyond these signs if you are hauling another passenger car?

Description
Art. 31 para. 1 pt. 1 of the Act of 20 June 1997, Road Traffic Act (Journal of Laws of 2012, item 1137, as amended) and § 58 para. 3 of the Regulation of the Ministers of Infrastructure and of Internal Affairs and Administration of 31 July 2002 on road signs and signals (Journal of Laws No. 170, item 1393, as amended)
Explanation
Correct answer: 60 km/h.
60 km/h. D-43 marks the end of the built-up area. Under Article 31(1)(1), a vehicle towing another motor vehicle is limited to 30 km/h in a built-up area and 60 km/h outside it, unless another limit or the conditions require a lower speed.