Final answer:
To best contrast the differing tones at the conclusion of each passage, one must compare the feelings or attitudes implied by the word choice and narrative style in 'Main Street' and 'A Hazard of New Fortunes'. Without the specific content of the passages, Option A seems the most fitting, contrasting a whimsical tone with a solemn tone.
Step-by-step explanation:
To contrast the differing tones at the conclusion of each passage, we need to consider the emotional impact conveyed by the use of specific words and phrases. The tone represents the author's attitude toward the subject or the audience and is expressed through stylistic elements such as word choice, sentence structure, and imagery. In the given examples of joyful and unhappy, we note the distinction made by the italicized words which imply a positive and negative mood respectively.
Considering the definitions and examples provided, we can analyze how each choice contrasts the tones of two literary works, Main Street and A Hazard of New Fortunes. Option A suggests a whimsical tone, generally lighthearted and playful, versus a solemn tone, which is serious and grave. This contrast fits the context if the former work concludes in a fanciful, light manner, while the latter ends with seriousness or gravity. Without the specific content of each passage, we can only give an approach based on the definition of these tones.