1. What key feature characterized the 1914 Movement War phase of WWI?
It was marked by rapid German advances halted by decisive battles like the Marne.
Explication
The 1914 Movement War was characterized by rapid German advances into France, which were halted at the Battle of the Marne, leading to a stalemate. This initial mobile phase was marked by swift offensives and decisive battles, not by static trench warfare or the extensive use of new weapons like tanks, which came later.