Final answer:
The light of a single candle in 'The Grapes of Wrath' symbolizes unity amongst the characters, highlighting the strength of community during the Great Depression.
Step-by-step explanation:
The symbolic light of a single candle in The Grapes of Wrath reflects the collective state of mind of unity. This notion is underlined by the major theme of the novel, where the characters, especially the Joad family, realize the importance of community and collective action in their struggle to survive the harsh realities of the Great Depression. The light symbolizes the shared hope and the togetherness that represent a beacon of solidarity in their dark times.