A.I. Explanation:

First sentence: Why this is the first line? This paragraph is the first because it introduces the main topic. It tells us about the decision to get a new pet. It does not need other sentences to understand it. It sets the stage for the story without going into details. Why other lines are not chosen? Paragraph 2 starts with "Meeting" which is not independent. Paragraph 3 starts with "The adoption process" which needs context. Paragraph 4 starts with "Bringing him home" which also needs prior information.

Concluding sentence: Why this is the last line? This paragraph is the last because it wraps up the story. It talks about the experience of bringing the pet home. It gives a sense of conclusion to the whole process.

Paragraph pairs:

• Pair 1 (Paragraph 1 → Paragraph 2): Paragraph 2 connects to Paragraph 1 because it continues the story. The first paragraph talks about deciding to get a pet, and the second talks about meeting pets. This shows a logical order of events.
• Pair 2 (Paragraph 2 → Paragraph 3): Paragraph 3 follows Paragraph 2 because after choosing a pet, the next step is the adoption process. This shows a clear logical order from choosing a pet to the steps needed to adopt it.
• Pair 3 (Paragraph 3 → Paragraph 4): Paragraph 4 connects to Paragraph 3 because after the adoption process, the next step is bringing the pet home. This shows a clear progression from getting ready to actually bringing the pet home.