A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first line because it introduces the main topic. It tells us about Marquez's arrival at Santa Elena. This is a new idea and does not need any other sentence for context. It does not start with a conjunction or use pronouns. Why other lines are not chosen? Paragraph 2 starts with "In 1571," which is a time reference and needs context. Paragraph 3 starts with "The town had flourished," which refers back to the town and needs prior information. Paragraph 4 starts with "In 1571," which also needs context.

Concluding sentence: Why this is the last line? This paragraph is the last line because it wraps up the information about the town. It gives a final important fact about Santa Elena becoming the capital. This shows the conclusion of the topic.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects with Paragraph 1 because it continues the story of Santa Elena. The action of erecting the fort follows Marquez's arrival. This shows a logical order of events.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 connects with Paragraph 2 because it explains more about the town. It gives background information about the town's growth and history. This shows a broader to specific strategy.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects with Paragraph 3 because it gives a specific event about the town. After explaining the town's growth, it tells us that it became the capital. This shows a logical order of events.