Final answer:
A student who refers to Hemingway's personal history as an ambulance driver during World War I and the war's influence on his writing in 'A Fareilwel to Arms' is most clearly using evidence to support the opinion that war greatly impacts individuals' minds.
Step-by-step explanation:
The student discussing Ernest Hemingway's A Farewell to Arms and reflecting on the impact of war on individuals is most clearly using evidence when they draw on the historical context and Hemingway's personal experiences. Hemingway served as an ambulance driver in World War I and was exposed to the horrors of war, which profoundly influenced his writing. This experience is mirrored in his narratives, particularly in A Farewell to Arms, which depicts the disillusionment and tragedy of war. The student using evidence might cite specific instances from Hemingway's life, such as his wartime service and its lasting effect on him, as well as elements from his novels that capture the psychological impact of war on his characters.