I think the letter B is the answer
The use of trench warfare on the Western Front was a major military strategy that led to four years of war on the Western Front during World War 1 (1914-1918). The armies which comprised of millions faced each other in a line of trenches which extended from the Belgian Coast through to the North Eastern part of France and Switzerland. This resulted in combat between the German troops and the Allied forces of Britain, France, and later the United States.
<span>Alternate energy: energy that is not popularly used and is usually environmentally sound, such as solar or wind </span>energy<span>(as opposed to fossil fuels).
SO... Biofuels are the only one that is not environmentally sound. Natural gas is no greenhouse gas and is safe for the environment. Solar power is power from the sun. Hydroelectricity is the power that comes from moving water AKA dams.</span>
The effect which it had on the economy was the <span>establishment of lending institutions across the continent, standardized methods of taxation and an increase in European trade.</span>
4. Pyramids were built as tombs for the pharaohs and their queens.
