Answer:
C. Today, chocolate is a common treat, and everyone gets to enjoy it.
Explanation:
The tone that I get from the paragraph is not exactly formal, but it's also not casual. The other 3 sentences are too casual and immature to fit the tone of the paragraph.
Answer:
Bicyclists should buy and wear helmets approved by the Consumer Product Safety Commission. These helmets should be adjusted for a good fit.
Explanation: