Answer:
C. Disillusionment in the years following World War I
Step-by-step explanation:
During the 1920s, these authors had similar themes that were featured in their works. Some of them are Disillusionment in the post-World War I community, the loss of identity and tradition, decadence, etc.
The "Lost Generation" is a name given to some group of writers and poets who were men and women that survived the Great War (World War I). Some of them were Ernest Hemingway, F. Scott Fitzgerald, T.S Elliot and Gertrude Stein.
The name "Lost Generation" was coined by Gertrude Stein.