Which prohibitions cease to apply when you see this sign?

You answered correctly. This sign means the end of all previous restrictions that were indicated by traffic signs—specifically, it ends overtaking prohibitions and speed limits that were set before. It does not mean the end of no parking zones, so selecting "No overtaking" and "Speed restrictions" is right. On roads in Germany, when you see this sign, normal rules apply again, such as the general speed limits if there are no other posted signs. Remember, parking restrictions typically remain unless another sign cancels them, so you should only choose the answers related to overtaking and speed when you see this question in the future.