What do the Walls of Babylon, the Ishtar Gate, and the Hanging Gardens have in common?

The Walls of Babylon, the Ishtar Gate, and the Hanging Gardens are all  located in Babylon, the capital city of Babylonia, and were all part of the wonders of the ancient world. However, the Ishtar gates and the Walls of Babylon has been replaced in the list of the 7 wonders of the ancient world by the lighthouse of Alexandria. The Ishtar Gate and the Hanging Gardens were built by king Nebuchadnezzar II in the capital of the Neo-Babylonian Empire. Nebuchadnezzar II also built the fortification for the Walls of Babylon

Explanation:

answer; (a) he was a u.s senator for 38 years;

d) post-world war i