A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first line because it introduces the main topic of watching elephants. It sets the scene without needing any prior context. It gives a broad overview of the situation. Why other lines are not chosen? Paragraph 2 starts with "Elephant expert lain Douglas-Hamilton told me..." which uses a pronoun and needs context. Paragraph 3 starts with "They would walk..." which refers back to a subject not yet introduced. Paragraph 4 starts with "Depending on how she was doing..." which also needs prior context. Paragraph 5 starts with "Sometimes the matriarch..." which assumes knowledge of the matriarch.

Concluding sentence: Why this is the last line? This paragraph is the last line because it wraps up the story about Babyl and the herd. It provides a specific action that shows care and support, which reflects the overall theme of the herd's loyalty.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): This pair connects because Paragraph 2 gives more details about the elephant mentioned in Paragraph 1. It follows the Broader to Specific Strategy, where the first paragraph introduces the general idea of watching elephants, and the second paragraph provides specific information about Babyl.
• Pair 2 (Paragraph 2 → Paragraph 3): This pair connects because Paragraph 3 explains what the herd does in relation to Babyl. It follows the Logical Order rule, as it shows the actions of the herd after explaining Babyl's condition.
• Pair 3 (Paragraph 3 → Paragraph 4): This pair connects because Paragraph 4 continues the thought from Paragraph 3. It explains what the herd does based on Babyl's condition. This follows the Cause and Effect Relationship rule, as the actions depend on her situation.
• Pair 4 (Paragraph 4 → Paragraph 5): This pair connects because Paragraph 5 gives an example of what the matriarch does based on Babyl's condition. It follows the Topic Example rule, where the last paragraph provides a specific instance related to the previous general statement.