Until modern times, most countries were ruled by

Most countries were ruled by some form of authoritarian governments. This mostly included kings or religious leaders. There was no democracy and no things such as election, but rather the monarch could do as he or as she pleased. This slowly started to change with addition of constitutions and development of republican sentiment around the times of the fall of Bastille and the separation of the US.

Answer(a); // soil salinization and waterlogging;