Option 1 -> Starting with "but John" without establishing context first makes the sentence incomplete and confusing.
Option 2 -> Beginning with "an inexhaustible supply" creates a fragment, and ending with "but John seemed to have" leaves the sentence incomplete.
Option 3 -> This arrangement creates a completely incoherent sentence with no logical flow or grammatical structure.
Option 4 -> Creates a complete, meaningful sentence: "Most people like to have a good rest after a long day of toiling at work but John seemed to have an inexhaustible supply of energy and enthusiasm" - proper contrast structure.
Hence, Option 4: (C), (A), (D), (B) -> This arrangement establishes what most people do first (rest after work), then uses "but" to create an effective contrast with John's unusual behavior (having endless energy), resulting in a grammatically correct and logically flowing sentence -> correct