Final answer:
During the Revolutionary War, the American forces at Valley Forge faced severe cold, hunger, pervading sicknesses, a lack of warm clothing, and difficulties in supply transportation due to icy roads.
Step-by-step explanation:
The winter at Valley Forge was indeed brutal for the American forces during the Revolutionary War. The challenges they faced included severe cold (A), an acute shortage of food (B), rampant sicknesses and disease (D), and their dire need for warm clothing (G). Additionally, icy roads made it extremely difficult to transport much-needed supplies (F). While the text does not explicitly mention the absence of a river for water (C) or the ability to spy on the British (E), we know from historical context that the encampment's location was strategically chosen with considerations for defense and visibility of British movements.