For this question the answer will be D.
What made it so hard for them to fight? well it was the raw temperature out on the battle field at a constant level and it also costed a lot of Russian life's also
D. It allows citizens of many European countries to freely travel across the continent.
The American Revolution was principally caused by colonial opposition to British attempts to impose greater control over the colonies and to make them repay the crown for its defense of them during the French and Indian War (1754–63).