Answer:
Unified command was decided to be necessary for the invasion, interservice rivalry over who it would be was so serious it derailed planning
The answers would be A and D. These are both true. It is not true however that working hours for children were restricted, nor kids had to be twelve to work. Many children worked at a very young age and didn't have an education.
The Schlieffen Plan was created in World War 1. It was used by the Germans to in order to fight France and Russia in the war. Germany was one of the central powers and was therefore in the "middle" of France and Russia. Russia was allied with France, so once a country declared war on France, the Russian army had to pitch in and help them fight.
Furthermore, the Germans declared war on France and Russia was ready to mobilize.
While Russia was mobilizing, the Germans wanted to fight one front at once quickly, so they could then fight Russia. They had to march through neutral Belgium and encircle the French army.
